1/*- 2 * Copyright (c) 2007-2009 3 * Swinburne University of Technology, Melbourne, Australia. 4 * Copyright (c) 2009-2010, The FreeBSD Foundation 5 * All rights reserved. 6 * 7 * Portions of this software were developed at the Centre for Advanced 8 * Internet Architectures, Swinburne University of Technology, Melbourne, 9 * Australia by Lawrence Stewart under sponsorship from the FreeBSD Foundation. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33/****************************************************** 34 * Statistical Information For TCP Research (SIFTR) 35 * 36 * A FreeBSD kernel module that adds very basic intrumentation to the 37 * TCP stack, allowing internal stats to be recorded to a log file 38 * for experimental, debugging and performance analysis purposes. 39 * 40 * SIFTR was first released in 2007 by James Healy and Lawrence Stewart whilst 41 * working on the NewTCP research project at Swinburne University of 42 * Technology's Centre for Advanced Internet Architectures, Melbourne, 43 * Australia, which was made possible in part by a grant from the Cisco 44 * University Research Program Fund at Community Foundation Silicon Valley. 45 * More details are available at: 46 * http://caia.swin.edu.au/urp/newtcp/ 47 * 48 * Work on SIFTR v1.2.x was sponsored by the FreeBSD Foundation as part of 49 * the "Enhancing the FreeBSD TCP Implementation" project 2008-2009. 50 * More details are available at: 51 * http://www.freebsdfoundation.org/ 52 * http://caia.swin.edu.au/freebsd/etcp09/ 53 * 54 * Lawrence Stewart is the current maintainer, and all contact regarding 55 * SIFTR should be directed to him via email: lastewart@swin.edu.au 56 * 57 * Initial release date: June 2007 58 * Most recent update: September 2010 59 ******************************************************/ 60 61#include <sys/cdefs.h> 62__FBSDID("$FreeBSD: stable/11/sys/netinet/siftr.c 343273 2019-01-21 19:33:05Z brooks $"); 63 64#include <sys/param.h> 65#include <sys/alq.h> 66#include <sys/errno.h> 67#include <sys/eventhandler.h> 68#include <sys/hash.h> 69#include <sys/kernel.h> 70#include <sys/kthread.h> 71#include <sys/lock.h> 72#include <sys/mbuf.h> 73#include <sys/module.h> 74#include <sys/mutex.h> 75#include <sys/pcpu.h> 76#include <sys/proc.h> 77#include <sys/sbuf.h> 78#include <sys/sdt.h> 79#include <sys/smp.h> 80#include <sys/socket.h> 81#include <sys/socketvar.h> 82#include <sys/sysctl.h> 83#include <sys/unistd.h> 84 85#include <net/if.h> 86#include <net/if_var.h> 87#include <net/pfil.h> 88 89#include <netinet/in.h> 90#include <netinet/in_kdtrace.h> 91#include <netinet/in_pcb.h> 92#include <netinet/in_systm.h> 93#include <netinet/in_var.h> 94#include <netinet/ip.h> 95#include <netinet/tcp_var.h> 96 97#ifdef SIFTR_IPV6 98#include <netinet/ip6.h> 99#include <netinet6/in6_pcb.h> 100#endif /* SIFTR_IPV6 */ 101 102#include <machine/in_cksum.h> 103 104/* 105 * Three digit version number refers to X.Y.Z where: 106 * X is the major version number 107 * Y is bumped to mark backwards incompatible changes 108 * Z is bumped to mark backwards compatible changes 109 */ 110#define V_MAJOR 1 111#define V_BACKBREAK 2 112#define V_BACKCOMPAT 4 113#define MODVERSION __CONCAT(V_MAJOR, __CONCAT(V_BACKBREAK, V_BACKCOMPAT)) 114#define MODVERSION_STR __XSTRING(V_MAJOR) "." __XSTRING(V_BACKBREAK) "." \ 115 __XSTRING(V_BACKCOMPAT) 116 117#define HOOK 0 118#define UNHOOK 1 119#define SIFTR_EXPECTED_MAX_TCP_FLOWS 65536 120#define SYS_NAME "FreeBSD" 121#define PACKET_TAG_SIFTR 100 122#define PACKET_COOKIE_SIFTR 21749576 123#define SIFTR_LOG_FILE_MODE 0644 124#define SIFTR_DISABLE 0 125#define SIFTR_ENABLE 1 126 127/* 128 * Hard upper limit on the length of log messages. Bump this up if you add new 129 * data fields such that the line length could exceed the below value. 130 */ 131#define MAX_LOG_MSG_LEN 200 132/* XXX: Make this a sysctl tunable. */ 133#define SIFTR_ALQ_BUFLEN (1000*MAX_LOG_MSG_LEN) 134 135/* 136 * 1 byte for IP version 137 * IPv4: src/dst IP (4+4) + src/dst port (2+2) = 12 bytes 138 * IPv6: src/dst IP (16+16) + src/dst port (2+2) = 36 bytes 139 */ 140#ifdef SIFTR_IPV6 141#define FLOW_KEY_LEN 37 142#else 143#define FLOW_KEY_LEN 13 144#endif 145 146#ifdef SIFTR_IPV6 147#define SIFTR_IPMODE 6 148#else 149#define SIFTR_IPMODE 4 150#endif 151 152/* useful macros */ 153#define UPPER_SHORT(X) (((X) & 0xFFFF0000) >> 16) 154#define LOWER_SHORT(X) ((X) & 0x0000FFFF) 155 156#define FIRST_OCTET(X) (((X) & 0xFF000000) >> 24) 157#define SECOND_OCTET(X) (((X) & 0x00FF0000) >> 16) 158#define THIRD_OCTET(X) (((X) & 0x0000FF00) >> 8) 159#define FOURTH_OCTET(X) ((X) & 0x000000FF) 160 161static MALLOC_DEFINE(M_SIFTR, "siftr", "dynamic memory used by SIFTR"); 162static MALLOC_DEFINE(M_SIFTR_PKTNODE, "siftr_pktnode", 163 "SIFTR pkt_node struct"); 164static MALLOC_DEFINE(M_SIFTR_HASHNODE, "siftr_hashnode", 165 "SIFTR flow_hash_node struct"); 166 167/* Used as links in the pkt manager queue. */ 168struct pkt_node { 169 /* Timestamp of pkt as noted in the pfil hook. */ 170 struct timeval tval; 171 /* Direction pkt is travelling; either PFIL_IN or PFIL_OUT. */ 172 uint8_t direction; 173 /* IP version pkt_node relates to; either INP_IPV4 or INP_IPV6. */ 174 uint8_t ipver; 175 /* Hash of the pkt which triggered the log message. */ 176 uint32_t hash; 177 /* Local/foreign IP address. */ 178#ifdef SIFTR_IPV6 179 uint32_t ip_laddr[4]; 180 uint32_t ip_faddr[4]; 181#else 182 uint8_t ip_laddr[4]; 183 uint8_t ip_faddr[4]; 184#endif 185 /* Local TCP port. */ 186 uint16_t tcp_localport; 187 /* Foreign TCP port. */ 188 uint16_t tcp_foreignport; 189 /* Congestion Window (bytes). */ 190 u_long snd_cwnd; 191 /* Sending Window (bytes). */ 192 u_long snd_wnd; 193 /* Receive Window (bytes). */ 194 u_long rcv_wnd; 195 /* Unused (was: Bandwidth Controlled Window (bytes)). */ 196 u_long snd_bwnd; 197 /* Slow Start Threshold (bytes). */ 198 u_long snd_ssthresh; 199 /* Current state of the TCP FSM. */ 200 int conn_state; 201 /* Max Segment Size (bytes). */ 202 u_int max_seg_size; 203 /* 204 * Smoothed RTT stored as found in the TCP control block 205 * in units of (TCP_RTT_SCALE*hz). 206 */ 207 int smoothed_rtt; 208 /* Is SACK enabled? */ 209 u_char sack_enabled; 210 /* Window scaling for snd window. */ 211 u_char snd_scale; 212 /* Window scaling for recv window. */ 213 u_char rcv_scale; 214 /* TCP control block flags. */ 215 u_int flags; 216 /* Retransmit timeout length. */ 217 int rxt_length; 218 /* Size of the TCP send buffer in bytes. */ 219 u_int snd_buf_hiwater; 220 /* Current num bytes in the send socket buffer. */ 221 u_int snd_buf_cc; 222 /* Size of the TCP receive buffer in bytes. */ 223 u_int rcv_buf_hiwater; 224 /* Current num bytes in the receive socket buffer. */ 225 u_int rcv_buf_cc; 226 /* Number of bytes inflight that we are waiting on ACKs for. */ 227 u_int sent_inflight_bytes; 228 /* Number of segments currently in the reassembly queue. */ 229 int t_segqlen; 230 /* Flowid for the connection. */ 231 u_int flowid; 232 /* Flow type for the connection. */ 233 u_int flowtype; 234 /* Link to next pkt_node in the list. */ 235 STAILQ_ENTRY(pkt_node) nodes; 236}; 237 238struct flow_hash_node 239{ 240 uint16_t counter; 241 uint8_t key[FLOW_KEY_LEN]; 242 LIST_ENTRY(flow_hash_node) nodes; 243}; 244 245struct siftr_stats 246{ 247 /* # TCP pkts seen by the SIFTR PFIL hooks, including any skipped. */ 248 uint64_t n_in; 249 uint64_t n_out; 250 /* # pkts skipped due to failed malloc calls. */ 251 uint32_t nskip_in_malloc; 252 uint32_t nskip_out_malloc; 253 /* # pkts skipped due to failed mtx acquisition. */ 254 uint32_t nskip_in_mtx; 255 uint32_t nskip_out_mtx; 256 /* # pkts skipped due to failed inpcb lookups. */ 257 uint32_t nskip_in_inpcb; 258 uint32_t nskip_out_inpcb; 259 /* # pkts skipped due to failed tcpcb lookups. */ 260 uint32_t nskip_in_tcpcb; 261 uint32_t nskip_out_tcpcb; 262 /* # pkts skipped due to stack reinjection. */ 263 uint32_t nskip_in_dejavu; 264 uint32_t nskip_out_dejavu; 265}; 266 267static DPCPU_DEFINE(struct siftr_stats, ss); 268 269static volatile unsigned int siftr_exit_pkt_manager_thread = 0; 270static unsigned int siftr_enabled = 0; 271static unsigned int siftr_pkts_per_log = 1; 272static unsigned int siftr_generate_hashes = 0; 273/* static unsigned int siftr_binary_log = 0; */ 274static char siftr_logfile[PATH_MAX] = "/var/log/siftr.log"; 275static char siftr_logfile_shadow[PATH_MAX] = "/var/log/siftr.log"; 276static u_long siftr_hashmask; 277STAILQ_HEAD(pkthead, pkt_node) pkt_queue = STAILQ_HEAD_INITIALIZER(pkt_queue); 278LIST_HEAD(listhead, flow_hash_node) *counter_hash; 279static int wait_for_pkt; 280static struct alq *siftr_alq = NULL; 281static struct mtx siftr_pkt_queue_mtx; 282static struct mtx siftr_pkt_mgr_mtx; 283static struct thread *siftr_pkt_manager_thr = NULL; 284/* 285 * pfil.h defines PFIL_IN as 1 and PFIL_OUT as 2, 286 * which we use as an index into this array. 287 */ 288static char direction[3] = {'\0', 'i','o'}; 289 290/* Required function prototypes. */ 291static int siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS); 292static int siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS); 293 294 295/* Declare the net.inet.siftr sysctl tree and populate it. */ 296 297SYSCTL_DECL(_net_inet_siftr); 298 299SYSCTL_NODE(_net_inet, OID_AUTO, siftr, CTLFLAG_RW, NULL, 300 "siftr related settings"); 301 302SYSCTL_PROC(_net_inet_siftr, OID_AUTO, enabled, CTLTYPE_UINT|CTLFLAG_RW, 303 &siftr_enabled, 0, &siftr_sysctl_enabled_handler, "IU", 304 "switch siftr module operations on/off"); 305 306SYSCTL_PROC(_net_inet_siftr, OID_AUTO, logfile, CTLTYPE_STRING|CTLFLAG_RW, 307 &siftr_logfile_shadow, sizeof(siftr_logfile_shadow), &siftr_sysctl_logfile_name_handler, 308 "A", "file to save siftr log messages to"); 309 310SYSCTL_UINT(_net_inet_siftr, OID_AUTO, ppl, CTLFLAG_RW, 311 &siftr_pkts_per_log, 1, 312 "number of packets between generating a log message"); 313 314SYSCTL_UINT(_net_inet_siftr, OID_AUTO, genhashes, CTLFLAG_RW, 315 &siftr_generate_hashes, 0, 316 "enable packet hash generation"); 317 318/* XXX: TODO 319SYSCTL_UINT(_net_inet_siftr, OID_AUTO, binary, CTLFLAG_RW, 320 &siftr_binary_log, 0, 321 "write log files in binary instead of ascii"); 322*/ 323 324 325/* Begin functions. */ 326 327static void 328siftr_process_pkt(struct pkt_node * pkt_node) 329{ 330 struct flow_hash_node *hash_node; 331 struct listhead *counter_list; 332 struct siftr_stats *ss; 333 struct ale *log_buf; 334 uint8_t key[FLOW_KEY_LEN]; 335 uint8_t found_match, key_offset; 336 337 hash_node = NULL; 338 ss = DPCPU_PTR(ss); 339 found_match = 0; 340 key_offset = 1; 341 342 /* 343 * Create the key that will be used to create a hash index 344 * into our hash table. Our key consists of: 345 * ipversion, localip, localport, foreignip, foreignport 346 */ 347 key[0] = pkt_node->ipver; 348 memcpy(key + key_offset, &pkt_node->ip_laddr, 349 sizeof(pkt_node->ip_laddr)); 350 key_offset += sizeof(pkt_node->ip_laddr); 351 memcpy(key + key_offset, &pkt_node->tcp_localport, 352 sizeof(pkt_node->tcp_localport)); 353 key_offset += sizeof(pkt_node->tcp_localport); 354 memcpy(key + key_offset, &pkt_node->ip_faddr, 355 sizeof(pkt_node->ip_faddr)); 356 key_offset += sizeof(pkt_node->ip_faddr); 357 memcpy(key + key_offset, &pkt_node->tcp_foreignport, 358 sizeof(pkt_node->tcp_foreignport)); 359 360 counter_list = counter_hash + 361 (hash32_buf(key, sizeof(key), 0) & siftr_hashmask); 362 363 /* 364 * If the list is not empty i.e. the hash index has 365 * been used by another flow previously. 366 */ 367 if (LIST_FIRST(counter_list) != NULL) { 368 /* 369 * Loop through the hash nodes in the list. 370 * There should normally only be 1 hash node in the list, 371 * except if there have been collisions at the hash index 372 * computed by hash32_buf(). 373 */ 374 LIST_FOREACH(hash_node, counter_list, nodes) { 375 /* 376 * Check if the key for the pkt we are currently 377 * processing is the same as the key stored in the 378 * hash node we are currently processing. 379 * If they are the same, then we've found the 380 * hash node that stores the counter for the flow 381 * the pkt belongs to. 382 */ 383 if (memcmp(hash_node->key, key, sizeof(key)) == 0) { 384 found_match = 1; 385 break; 386 } 387 } 388 } 389 390 /* If this flow hash hasn't been seen before or we have a collision. */ 391 if (hash_node == NULL || !found_match) { 392 /* Create a new hash node to store the flow's counter. */ 393 hash_node = malloc(sizeof(struct flow_hash_node), 394 M_SIFTR_HASHNODE, M_WAITOK); 395 396 if (hash_node != NULL) { 397 /* Initialise our new hash node list entry. */ 398 hash_node->counter = 0; 399 memcpy(hash_node->key, key, sizeof(key)); 400 LIST_INSERT_HEAD(counter_list, hash_node, nodes); 401 } else { 402 /* Malloc failed. */ 403 if (pkt_node->direction == PFIL_IN) 404 ss->nskip_in_malloc++; 405 else 406 ss->nskip_out_malloc++; 407 408 return; 409 } 410 } else if (siftr_pkts_per_log > 1) { 411 /* 412 * Taking the remainder of the counter divided 413 * by the current value of siftr_pkts_per_log 414 * and storing that in counter provides a neat 415 * way to modulate the frequency of log 416 * messages being written to the log file. 417 */ 418 hash_node->counter = (hash_node->counter + 1) % 419 siftr_pkts_per_log; 420 421 /* 422 * If we have not seen enough packets since the last time 423 * we wrote a log message for this connection, return. 424 */ 425 if (hash_node->counter > 0) 426 return; 427 } 428 429 log_buf = alq_getn(siftr_alq, MAX_LOG_MSG_LEN, ALQ_WAITOK); 430 431 if (log_buf == NULL) 432 return; /* Should only happen if the ALQ is shutting down. */ 433 434#ifdef SIFTR_IPV6 435 pkt_node->ip_laddr[3] = ntohl(pkt_node->ip_laddr[3]); 436 pkt_node->ip_faddr[3] = ntohl(pkt_node->ip_faddr[3]); 437 438 if (pkt_node->ipver == INP_IPV6) { /* IPv6 packet */ 439 pkt_node->ip_laddr[0] = ntohl(pkt_node->ip_laddr[0]); 440 pkt_node->ip_laddr[1] = ntohl(pkt_node->ip_laddr[1]); 441 pkt_node->ip_laddr[2] = ntohl(pkt_node->ip_laddr[2]); 442 pkt_node->ip_faddr[0] = ntohl(pkt_node->ip_faddr[0]); 443 pkt_node->ip_faddr[1] = ntohl(pkt_node->ip_faddr[1]); 444 pkt_node->ip_faddr[2] = ntohl(pkt_node->ip_faddr[2]); 445 446 /* Construct an IPv6 log message. */ 447 log_buf->ae_bytesused = snprintf(log_buf->ae_data, 448 MAX_LOG_MSG_LEN, 449 "%c,0x%08x,%zd.%06ld,%x:%x:%x:%x:%x:%x:%x:%x,%u,%x:%x:%x:" 450 "%x:%x:%x:%x:%x,%u,%ld,%ld,%ld,%ld,%ld,%u,%u,%u,%u,%u,%u," 451 "%u,%d,%u,%u,%u,%u,%u,%u,%u,%u\n", 452 direction[pkt_node->direction], 453 pkt_node->hash, 454 pkt_node->tval.tv_sec, 455 pkt_node->tval.tv_usec, 456 UPPER_SHORT(pkt_node->ip_laddr[0]), 457 LOWER_SHORT(pkt_node->ip_laddr[0]), 458 UPPER_SHORT(pkt_node->ip_laddr[1]), 459 LOWER_SHORT(pkt_node->ip_laddr[1]), 460 UPPER_SHORT(pkt_node->ip_laddr[2]), 461 LOWER_SHORT(pkt_node->ip_laddr[2]), 462 UPPER_SHORT(pkt_node->ip_laddr[3]), 463 LOWER_SHORT(pkt_node->ip_laddr[3]), 464 ntohs(pkt_node->tcp_localport), 465 UPPER_SHORT(pkt_node->ip_faddr[0]), 466 LOWER_SHORT(pkt_node->ip_faddr[0]), 467 UPPER_SHORT(pkt_node->ip_faddr[1]), 468 LOWER_SHORT(pkt_node->ip_faddr[1]), 469 UPPER_SHORT(pkt_node->ip_faddr[2]), 470 LOWER_SHORT(pkt_node->ip_faddr[2]), 471 UPPER_SHORT(pkt_node->ip_faddr[3]), 472 LOWER_SHORT(pkt_node->ip_faddr[3]), 473 ntohs(pkt_node->tcp_foreignport), 474 pkt_node->snd_ssthresh, 475 pkt_node->snd_cwnd, 476 pkt_node->snd_bwnd, 477 pkt_node->snd_wnd, 478 pkt_node->rcv_wnd, 479 pkt_node->snd_scale, 480 pkt_node->rcv_scale, 481 pkt_node->conn_state, 482 pkt_node->max_seg_size, 483 pkt_node->smoothed_rtt, 484 pkt_node->sack_enabled, 485 pkt_node->flags, 486 pkt_node->rxt_length, 487 pkt_node->snd_buf_hiwater, 488 pkt_node->snd_buf_cc, 489 pkt_node->rcv_buf_hiwater, 490 pkt_node->rcv_buf_cc, 491 pkt_node->sent_inflight_bytes, 492 pkt_node->t_segqlen, 493 pkt_node->flowid, 494 pkt_node->flowtype); 495 } else { /* IPv4 packet */ 496 pkt_node->ip_laddr[0] = FIRST_OCTET(pkt_node->ip_laddr[3]); 497 pkt_node->ip_laddr[1] = SECOND_OCTET(pkt_node->ip_laddr[3]); 498 pkt_node->ip_laddr[2] = THIRD_OCTET(pkt_node->ip_laddr[3]); 499 pkt_node->ip_laddr[3] = FOURTH_OCTET(pkt_node->ip_laddr[3]); 500 pkt_node->ip_faddr[0] = FIRST_OCTET(pkt_node->ip_faddr[3]); 501 pkt_node->ip_faddr[1] = SECOND_OCTET(pkt_node->ip_faddr[3]); 502 pkt_node->ip_faddr[2] = THIRD_OCTET(pkt_node->ip_faddr[3]); 503 pkt_node->ip_faddr[3] = FOURTH_OCTET(pkt_node->ip_faddr[3]); 504#endif /* SIFTR_IPV6 */ 505 506 /* Construct an IPv4 log message. */ 507 log_buf->ae_bytesused = snprintf(log_buf->ae_data, 508 MAX_LOG_MSG_LEN, 509 "%c,0x%08x,%jd.%06ld,%u.%u.%u.%u,%u,%u.%u.%u.%u,%u,%ld,%ld," 510 "%ld,%ld,%ld,%u,%u,%u,%u,%u,%u,%u,%d,%u,%u,%u,%u,%u,%u,%u,%u\n", 511 direction[pkt_node->direction], 512 pkt_node->hash, 513 (intmax_t)pkt_node->tval.tv_sec, 514 pkt_node->tval.tv_usec, 515 pkt_node->ip_laddr[0], 516 pkt_node->ip_laddr[1], 517 pkt_node->ip_laddr[2], 518 pkt_node->ip_laddr[3], 519 ntohs(pkt_node->tcp_localport), 520 pkt_node->ip_faddr[0], 521 pkt_node->ip_faddr[1], 522 pkt_node->ip_faddr[2], 523 pkt_node->ip_faddr[3], 524 ntohs(pkt_node->tcp_foreignport), 525 pkt_node->snd_ssthresh, 526 pkt_node->snd_cwnd, 527 pkt_node->snd_bwnd, 528 pkt_node->snd_wnd, 529 pkt_node->rcv_wnd, 530 pkt_node->snd_scale, 531 pkt_node->rcv_scale, 532 pkt_node->conn_state, 533 pkt_node->max_seg_size, 534 pkt_node->smoothed_rtt, 535 pkt_node->sack_enabled, 536 pkt_node->flags, 537 pkt_node->rxt_length, 538 pkt_node->snd_buf_hiwater, 539 pkt_node->snd_buf_cc, 540 pkt_node->rcv_buf_hiwater, 541 pkt_node->rcv_buf_cc, 542 pkt_node->sent_inflight_bytes, 543 pkt_node->t_segqlen, 544 pkt_node->flowid, 545 pkt_node->flowtype); 546#ifdef SIFTR_IPV6 547 } 548#endif 549 550 alq_post_flags(siftr_alq, log_buf, 0); 551} 552 553 554static void 555siftr_pkt_manager_thread(void *arg) 556{ 557 STAILQ_HEAD(pkthead, pkt_node) tmp_pkt_queue = 558 STAILQ_HEAD_INITIALIZER(tmp_pkt_queue); 559 struct pkt_node *pkt_node, *pkt_node_temp; 560 uint8_t draining; 561 562 draining = 2; 563 564 mtx_lock(&siftr_pkt_mgr_mtx); 565 566 /* draining == 0 when queue has been flushed and it's safe to exit. */ 567 while (draining) { 568 /* 569 * Sleep until we are signalled to wake because thread has 570 * been told to exit or until 1 tick has passed. 571 */ 572 mtx_sleep(&wait_for_pkt, &siftr_pkt_mgr_mtx, PWAIT, "pktwait", 573 1); 574 575 /* Gain exclusive access to the pkt_node queue. */ 576 mtx_lock(&siftr_pkt_queue_mtx); 577 578 /* 579 * Move pkt_queue to tmp_pkt_queue, which leaves 580 * pkt_queue empty and ready to receive more pkt_nodes. 581 */ 582 STAILQ_CONCAT(&tmp_pkt_queue, &pkt_queue); 583 584 /* 585 * We've finished making changes to the list. Unlock it 586 * so the pfil hooks can continue queuing pkt_nodes. 587 */ 588 mtx_unlock(&siftr_pkt_queue_mtx); 589 590 /* 591 * We can't hold a mutex whilst calling siftr_process_pkt 592 * because ALQ might sleep waiting for buffer space. 593 */ 594 mtx_unlock(&siftr_pkt_mgr_mtx); 595 596 /* Flush all pkt_nodes to the log file. */ 597 STAILQ_FOREACH_SAFE(pkt_node, &tmp_pkt_queue, nodes, 598 pkt_node_temp) { 599 siftr_process_pkt(pkt_node); 600 STAILQ_REMOVE_HEAD(&tmp_pkt_queue, nodes); 601 free(pkt_node, M_SIFTR_PKTNODE); 602 } 603 604 KASSERT(STAILQ_EMPTY(&tmp_pkt_queue), 605 ("SIFTR tmp_pkt_queue not empty after flush")); 606 607 mtx_lock(&siftr_pkt_mgr_mtx); 608 609 /* 610 * If siftr_exit_pkt_manager_thread gets set during the window 611 * where we are draining the tmp_pkt_queue above, there might 612 * still be pkts in pkt_queue that need to be drained. 613 * Allow one further iteration to occur after 614 * siftr_exit_pkt_manager_thread has been set to ensure 615 * pkt_queue is completely empty before we kill the thread. 616 * 617 * siftr_exit_pkt_manager_thread is set only after the pfil 618 * hooks have been removed, so only 1 extra iteration 619 * is needed to drain the queue. 620 */ 621 if (siftr_exit_pkt_manager_thread) 622 draining--; 623 } 624 625 mtx_unlock(&siftr_pkt_mgr_mtx); 626 627 /* Calls wakeup on this thread's struct thread ptr. */ 628 kthread_exit(); 629} 630 631 632static uint32_t 633hash_pkt(struct mbuf *m, uint32_t offset) 634{ 635 uint32_t hash; 636 637 hash = 0; 638 639 while (m != NULL && offset > m->m_len) { 640 /* 641 * The IP packet payload does not start in this mbuf, so 642 * need to figure out which mbuf it starts in and what offset 643 * into the mbuf's data region the payload starts at. 644 */ 645 offset -= m->m_len; 646 m = m->m_next; 647 } 648 649 while (m != NULL) { 650 /* Ensure there is data in the mbuf */ 651 if ((m->m_len - offset) > 0) 652 hash = hash32_buf(m->m_data + offset, 653 m->m_len - offset, hash); 654 655 m = m->m_next; 656 offset = 0; 657 } 658 659 return (hash); 660} 661 662 663/* 664 * Check if a given mbuf has the SIFTR mbuf tag. If it does, log the fact that 665 * it's a reinjected packet and return. If it doesn't, tag the mbuf and return. 666 * Return value >0 means the caller should skip processing this mbuf. 667 */ 668static inline int 669siftr_chkreinject(struct mbuf *m, int dir, struct siftr_stats *ss) 670{ 671 if (m_tag_locate(m, PACKET_COOKIE_SIFTR, PACKET_TAG_SIFTR, NULL) 672 != NULL) { 673 if (dir == PFIL_IN) 674 ss->nskip_in_dejavu++; 675 else 676 ss->nskip_out_dejavu++; 677 678 return (1); 679 } else { 680 struct m_tag *tag = m_tag_alloc(PACKET_COOKIE_SIFTR, 681 PACKET_TAG_SIFTR, 0, M_NOWAIT); 682 if (tag == NULL) { 683 if (dir == PFIL_IN) 684 ss->nskip_in_malloc++; 685 else 686 ss->nskip_out_malloc++; 687 688 return (1); 689 } 690 691 m_tag_prepend(m, tag); 692 } 693 694 return (0); 695} 696 697 698/* 699 * Look up an inpcb for a packet. Return the inpcb pointer if found, or NULL 700 * otherwise. 701 */ 702static inline struct inpcb * 703siftr_findinpcb(int ipver, struct ip *ip, struct mbuf *m, uint16_t sport, 704 uint16_t dport, int dir, struct siftr_stats *ss) 705{ 706 struct inpcb *inp; 707 708 /* We need the tcbinfo lock. */ 709 INP_INFO_UNLOCK_ASSERT(&V_tcbinfo); 710 711 if (dir == PFIL_IN) 712 inp = (ipver == INP_IPV4 ? 713 in_pcblookup(&V_tcbinfo, ip->ip_src, sport, ip->ip_dst, 714 dport, INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif) 715 : 716#ifdef SIFTR_IPV6 717 in6_pcblookup(&V_tcbinfo, 718 &((struct ip6_hdr *)ip)->ip6_src, sport, 719 &((struct ip6_hdr *)ip)->ip6_dst, dport, INPLOOKUP_RLOCKPCB, 720 m->m_pkthdr.rcvif) 721#else 722 NULL 723#endif 724 ); 725 726 else 727 inp = (ipver == INP_IPV4 ? 728 in_pcblookup(&V_tcbinfo, ip->ip_dst, dport, ip->ip_src, 729 sport, INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif) 730 : 731#ifdef SIFTR_IPV6 732 in6_pcblookup(&V_tcbinfo, 733 &((struct ip6_hdr *)ip)->ip6_dst, dport, 734 &((struct ip6_hdr *)ip)->ip6_src, sport, INPLOOKUP_RLOCKPCB, 735 m->m_pkthdr.rcvif) 736#else 737 NULL 738#endif 739 ); 740 741 /* If we can't find the inpcb, bail. */ 742 if (inp == NULL) { 743 if (dir == PFIL_IN) 744 ss->nskip_in_inpcb++; 745 else 746 ss->nskip_out_inpcb++; 747 } 748 749 return (inp); 750} 751 752 753static inline void 754siftr_siftdata(struct pkt_node *pn, struct inpcb *inp, struct tcpcb *tp, 755 int ipver, int dir, int inp_locally_locked) 756{ 757#ifdef SIFTR_IPV6 758 if (ipver == INP_IPV4) { 759 pn->ip_laddr[3] = inp->inp_laddr.s_addr; 760 pn->ip_faddr[3] = inp->inp_faddr.s_addr; 761#else 762 *((uint32_t *)pn->ip_laddr) = inp->inp_laddr.s_addr; 763 *((uint32_t *)pn->ip_faddr) = inp->inp_faddr.s_addr; 764#endif 765#ifdef SIFTR_IPV6 766 } else { 767 pn->ip_laddr[0] = inp->in6p_laddr.s6_addr32[0]; 768 pn->ip_laddr[1] = inp->in6p_laddr.s6_addr32[1]; 769 pn->ip_laddr[2] = inp->in6p_laddr.s6_addr32[2]; 770 pn->ip_laddr[3] = inp->in6p_laddr.s6_addr32[3]; 771 pn->ip_faddr[0] = inp->in6p_faddr.s6_addr32[0]; 772 pn->ip_faddr[1] = inp->in6p_faddr.s6_addr32[1]; 773 pn->ip_faddr[2] = inp->in6p_faddr.s6_addr32[2]; 774 pn->ip_faddr[3] = inp->in6p_faddr.s6_addr32[3]; 775 } 776#endif 777 pn->tcp_localport = inp->inp_lport; 778 pn->tcp_foreignport = inp->inp_fport; 779 pn->snd_cwnd = tp->snd_cwnd; 780 pn->snd_wnd = tp->snd_wnd; 781 pn->rcv_wnd = tp->rcv_wnd; 782 pn->snd_bwnd = 0; /* Unused, kept for compat. */ 783 pn->snd_ssthresh = tp->snd_ssthresh; 784 pn->snd_scale = tp->snd_scale; 785 pn->rcv_scale = tp->rcv_scale; 786 pn->conn_state = tp->t_state; 787 pn->max_seg_size = tp->t_maxseg; 788 pn->smoothed_rtt = tp->t_srtt; 789 pn->sack_enabled = (tp->t_flags & TF_SACK_PERMIT) != 0; 790 pn->flags = tp->t_flags; 791 pn->rxt_length = tp->t_rxtcur; 792 pn->snd_buf_hiwater = inp->inp_socket->so_snd.sb_hiwat; 793 pn->snd_buf_cc = sbused(&inp->inp_socket->so_snd); 794 pn->rcv_buf_hiwater = inp->inp_socket->so_rcv.sb_hiwat; 795 pn->rcv_buf_cc = sbused(&inp->inp_socket->so_rcv); 796 pn->sent_inflight_bytes = tp->snd_max - tp->snd_una; 797 pn->t_segqlen = tp->t_segqlen; 798 pn->flowid = inp->inp_flowid; 799 pn->flowtype = inp->inp_flowtype; 800 801 /* We've finished accessing the tcb so release the lock. */ 802 if (inp_locally_locked) 803 INP_RUNLOCK(inp); 804 805 pn->ipver = ipver; 806 pn->direction = dir; 807 808 /* 809 * Significantly more accurate than using getmicrotime(), but slower! 810 * Gives true microsecond resolution at the expense of a hit to 811 * maximum pps throughput processing when SIFTR is loaded and enabled. 812 */ 813 microtime(&pn->tval); 814 TCP_PROBE1(siftr, &pn); 815 816} 817 818 819/* 820 * pfil hook that is called for each IPv4 packet making its way through the 821 * stack in either direction. 822 * The pfil subsystem holds a non-sleepable mutex somewhere when 823 * calling our hook function, so we can't sleep at all. 824 * It's very important to use the M_NOWAIT flag with all function calls 825 * that support it so that they won't sleep, otherwise you get a panic. 826 */ 827static int 828siftr_chkpkt(void *arg, struct mbuf **m, struct ifnet *ifp, int dir, 829 struct inpcb *inp) 830{ 831 struct pkt_node *pn; 832 struct ip *ip; 833 struct tcphdr *th; 834 struct tcpcb *tp; 835 struct siftr_stats *ss; 836 unsigned int ip_hl; 837 int inp_locally_locked; 838 839 inp_locally_locked = 0; 840 ss = DPCPU_PTR(ss); 841 842 /* 843 * m_pullup is not required here because ip_{input|output} 844 * already do the heavy lifting for us. 845 */ 846 847 ip = mtod(*m, struct ip *); 848 849 /* Only continue processing if the packet is TCP. */ 850 if (ip->ip_p != IPPROTO_TCP) 851 goto ret; 852 853 /* 854 * If a kernel subsystem reinjects packets into the stack, our pfil 855 * hook will be called multiple times for the same packet. 856 * Make sure we only process unique packets. 857 */ 858 if (siftr_chkreinject(*m, dir, ss)) 859 goto ret; 860 861 if (dir == PFIL_IN) 862 ss->n_in++; 863 else 864 ss->n_out++; 865 866 /* 867 * Create a tcphdr struct starting at the correct offset 868 * in the IP packet. ip->ip_hl gives the ip header length 869 * in 4-byte words, so multiply it to get the size in bytes. 870 */ 871 ip_hl = (ip->ip_hl << 2); 872 th = (struct tcphdr *)((caddr_t)ip + ip_hl); 873 874 /* 875 * If the pfil hooks don't provide a pointer to the 876 * inpcb, we need to find it ourselves and lock it. 877 */ 878 if (!inp) { 879 /* Find the corresponding inpcb for this pkt. */ 880 inp = siftr_findinpcb(INP_IPV4, ip, *m, th->th_sport, 881 th->th_dport, dir, ss); 882 883 if (inp == NULL) 884 goto ret; 885 else 886 inp_locally_locked = 1; 887 } 888 889 INP_LOCK_ASSERT(inp); 890 891 /* Find the TCP control block that corresponds with this packet */ 892 tp = intotcpcb(inp); 893 894 /* 895 * If we can't find the TCP control block (happens occasionaly for a 896 * packet sent during the shutdown phase of a TCP connection), 897 * or we're in the timewait state, bail 898 */ 899 if (tp == NULL || inp->inp_flags & INP_TIMEWAIT) { 900 if (dir == PFIL_IN) 901 ss->nskip_in_tcpcb++; 902 else 903 ss->nskip_out_tcpcb++; 904 905 goto inp_unlock; 906 } 907 908 pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO); 909 910 if (pn == NULL) { 911 if (dir == PFIL_IN) 912 ss->nskip_in_malloc++; 913 else 914 ss->nskip_out_malloc++; 915 916 goto inp_unlock; 917 } 918 919 siftr_siftdata(pn, inp, tp, INP_IPV4, dir, inp_locally_locked); 920 921 if (siftr_generate_hashes) { 922 if ((*m)->m_pkthdr.csum_flags & CSUM_TCP) { 923 /* 924 * For outbound packets, the TCP checksum isn't 925 * calculated yet. This is a problem for our packet 926 * hashing as the receiver will calc a different hash 927 * to ours if we don't include the correct TCP checksum 928 * in the bytes being hashed. To work around this 929 * problem, we manually calc the TCP checksum here in 930 * software. We unset the CSUM_TCP flag so the lower 931 * layers don't recalc it. 932 */ 933 (*m)->m_pkthdr.csum_flags &= ~CSUM_TCP; 934 935 /* 936 * Calculate the TCP checksum in software and assign 937 * to correct TCP header field, which will follow the 938 * packet mbuf down the stack. The trick here is that 939 * tcp_output() sets th->th_sum to the checksum of the 940 * pseudo header for us already. Because of the nature 941 * of the checksumming algorithm, we can sum over the 942 * entire IP payload (i.e. TCP header and data), which 943 * will include the already calculated pseduo header 944 * checksum, thus giving us the complete TCP checksum. 945 * 946 * To put it in simple terms, if checksum(1,2,3,4)=10, 947 * then checksum(1,2,3,4,5) == checksum(10,5). 948 * This property is what allows us to "cheat" and 949 * checksum only the IP payload which has the TCP 950 * th_sum field populated with the pseudo header's 951 * checksum, and not need to futz around checksumming 952 * pseudo header bytes and TCP header/data in one hit. 953 * Refer to RFC 1071 for more info. 954 * 955 * NB: in_cksum_skip(struct mbuf *m, int len, int skip) 956 * in_cksum_skip 2nd argument is NOT the number of 957 * bytes to read from the mbuf at "skip" bytes offset 958 * from the start of the mbuf (very counter intuitive!). 959 * The number of bytes to read is calculated internally 960 * by the function as len-skip i.e. to sum over the IP 961 * payload (TCP header + data) bytes, it is INCORRECT 962 * to call the function like this: 963 * in_cksum_skip(at, ip->ip_len - offset, offset) 964 * Rather, it should be called like this: 965 * in_cksum_skip(at, ip->ip_len, offset) 966 * which means read "ip->ip_len - offset" bytes from 967 * the mbuf cluster "at" at offset "offset" bytes from 968 * the beginning of the "at" mbuf's data pointer. 969 */ 970 th->th_sum = in_cksum_skip(*m, ntohs(ip->ip_len), 971 ip_hl); 972 } 973 974 /* 975 * XXX: Having to calculate the checksum in software and then 976 * hash over all bytes is really inefficient. Would be nice to 977 * find a way to create the hash and checksum in the same pass 978 * over the bytes. 979 */ 980 pn->hash = hash_pkt(*m, ip_hl); 981 } 982 983 mtx_lock(&siftr_pkt_queue_mtx); 984 STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes); 985 mtx_unlock(&siftr_pkt_queue_mtx); 986 goto ret; 987 988inp_unlock: 989 if (inp_locally_locked) 990 INP_RUNLOCK(inp); 991 992ret: 993 /* Returning 0 ensures pfil will not discard the pkt */ 994 return (0); 995} 996 997 998#ifdef SIFTR_IPV6 999static int 1000siftr_chkpkt6(void *arg, struct mbuf **m, struct ifnet *ifp, int dir, 1001 struct inpcb *inp) 1002{ 1003 struct pkt_node *pn; 1004 struct ip6_hdr *ip6; 1005 struct tcphdr *th; 1006 struct tcpcb *tp; 1007 struct siftr_stats *ss; 1008 unsigned int ip6_hl; 1009 int inp_locally_locked; 1010 1011 inp_locally_locked = 0; 1012 ss = DPCPU_PTR(ss); 1013 1014 /* 1015 * m_pullup is not required here because ip6_{input|output} 1016 * already do the heavy lifting for us. 1017 */ 1018 1019 ip6 = mtod(*m, struct ip6_hdr *); 1020 1021 /* 1022 * Only continue processing if the packet is TCP 1023 * XXX: We should follow the next header fields 1024 * as shown on Pg 6 RFC 2460, but right now we'll 1025 * only check pkts that have no extension headers. 1026 */ 1027 if (ip6->ip6_nxt != IPPROTO_TCP) 1028 goto ret6; 1029 1030 /* 1031 * If a kernel subsystem reinjects packets into the stack, our pfil 1032 * hook will be called multiple times for the same packet. 1033 * Make sure we only process unique packets. 1034 */ 1035 if (siftr_chkreinject(*m, dir, ss)) 1036 goto ret6; 1037 1038 if (dir == PFIL_IN) 1039 ss->n_in++; 1040 else 1041 ss->n_out++; 1042 1043 ip6_hl = sizeof(struct ip6_hdr); 1044 1045 /* 1046 * Create a tcphdr struct starting at the correct offset 1047 * in the ipv6 packet. ip->ip_hl gives the ip header length 1048 * in 4-byte words, so multiply it to get the size in bytes. 1049 */ 1050 th = (struct tcphdr *)((caddr_t)ip6 + ip6_hl); 1051 1052 /* 1053 * For inbound packets, the pfil hooks don't provide a pointer to the 1054 * inpcb, so we need to find it ourselves and lock it. 1055 */ 1056 if (!inp) { 1057 /* Find the corresponding inpcb for this pkt. */ 1058 inp = siftr_findinpcb(INP_IPV6, (struct ip *)ip6, *m, 1059 th->th_sport, th->th_dport, dir, ss); 1060 1061 if (inp == NULL) 1062 goto ret6; 1063 else 1064 inp_locally_locked = 1; 1065 } 1066 1067 /* Find the TCP control block that corresponds with this packet. */ 1068 tp = intotcpcb(inp); 1069 1070 /* 1071 * If we can't find the TCP control block (happens occasionaly for a 1072 * packet sent during the shutdown phase of a TCP connection), 1073 * or we're in the timewait state, bail. 1074 */ 1075 if (tp == NULL || inp->inp_flags & INP_TIMEWAIT) { 1076 if (dir == PFIL_IN) 1077 ss->nskip_in_tcpcb++; 1078 else 1079 ss->nskip_out_tcpcb++; 1080 1081 goto inp_unlock6; 1082 } 1083 1084 pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO); 1085 1086 if (pn == NULL) { 1087 if (dir == PFIL_IN) 1088 ss->nskip_in_malloc++; 1089 else 1090 ss->nskip_out_malloc++; 1091 1092 goto inp_unlock6; 1093 } 1094 1095 siftr_siftdata(pn, inp, tp, INP_IPV6, dir, inp_locally_locked); 1096 1097 /* XXX: Figure out how to generate hashes for IPv6 packets. */ 1098 1099 mtx_lock(&siftr_pkt_queue_mtx); 1100 STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes); 1101 mtx_unlock(&siftr_pkt_queue_mtx); 1102 goto ret6; 1103 1104inp_unlock6: 1105 if (inp_locally_locked) 1106 INP_RUNLOCK(inp); 1107 1108ret6: 1109 /* Returning 0 ensures pfil will not discard the pkt. */ 1110 return (0); 1111} 1112#endif /* #ifdef SIFTR_IPV6 */ 1113 1114 1115static int 1116siftr_pfil(int action) 1117{ 1118 struct pfil_head *pfh_inet; 1119#ifdef SIFTR_IPV6 1120 struct pfil_head *pfh_inet6; 1121#endif 1122 VNET_ITERATOR_DECL(vnet_iter); 1123 1124 VNET_LIST_RLOCK(); 1125 VNET_FOREACH(vnet_iter) { 1126 CURVNET_SET(vnet_iter); 1127 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET); 1128#ifdef SIFTR_IPV6 1129 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6); 1130#endif 1131 1132 if (action == HOOK) { 1133 pfil_add_hook(siftr_chkpkt, NULL, 1134 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet); 1135#ifdef SIFTR_IPV6 1136 pfil_add_hook(siftr_chkpkt6, NULL, 1137 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet6); 1138#endif 1139 } else if (action == UNHOOK) { 1140 pfil_remove_hook(siftr_chkpkt, NULL, 1141 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet); 1142#ifdef SIFTR_IPV6 1143 pfil_remove_hook(siftr_chkpkt6, NULL, 1144 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet6); 1145#endif 1146 } 1147 CURVNET_RESTORE(); 1148 } 1149 VNET_LIST_RUNLOCK(); 1150 1151 return (0); 1152} 1153 1154 1155static int 1156siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS) 1157{ 1158 struct alq *new_alq; 1159 int error; 1160 1161 error = sysctl_handle_string(oidp, arg1, arg2, req); 1162 1163 /* Check for error or same filename */ 1164 if (error != 0 || req->newptr == NULL || 1165 strncmp(siftr_logfile, arg1, arg2) == 0) 1166 goto done; 1167 1168 /* Filname changed */ 1169 error = alq_open(&new_alq, arg1, curthread->td_ucred, 1170 SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0); 1171 if (error != 0) 1172 goto done; 1173 1174 /* 1175 * If disabled, siftr_alq == NULL so we simply close 1176 * the alq as we've proved it can be opened. 1177 * If enabled, close the existing alq and switch the old 1178 * for the new. 1179 */ 1180 if (siftr_alq == NULL) { 1181 alq_close(new_alq); 1182 } else { 1183 alq_close(siftr_alq); 1184 siftr_alq = new_alq; 1185 } 1186 1187 /* Update filename upon success */ 1188 strlcpy(siftr_logfile, arg1, arg2); 1189done: 1190 return (error); 1191} 1192 1193static int 1194siftr_manage_ops(uint8_t action) 1195{ 1196 struct siftr_stats totalss; 1197 struct timeval tval; 1198 struct flow_hash_node *counter, *tmp_counter; 1199 struct sbuf *s; 1200 int i, key_index, ret, error; 1201 uint32_t bytes_to_write, total_skipped_pkts; 1202 uint16_t lport, fport; 1203 uint8_t *key, ipver; 1204 1205#ifdef SIFTR_IPV6 1206 uint32_t laddr[4]; 1207 uint32_t faddr[4]; 1208#else 1209 uint8_t laddr[4]; 1210 uint8_t faddr[4]; 1211#endif 1212 1213 error = 0; 1214 total_skipped_pkts = 0; 1215 1216 /* Init an autosizing sbuf that initially holds 200 chars. */ 1217 if ((s = sbuf_new(NULL, NULL, 200, SBUF_AUTOEXTEND)) == NULL) 1218 return (-1); 1219 1220 if (action == SIFTR_ENABLE && siftr_pkt_manager_thr == NULL) { 1221 /* 1222 * Create our alq 1223 * XXX: We should abort if alq_open fails! 1224 */ 1225 alq_open(&siftr_alq, siftr_logfile, curthread->td_ucred, 1226 SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0); 1227 1228 STAILQ_INIT(&pkt_queue); 1229 1230 DPCPU_ZERO(ss); 1231 1232 siftr_exit_pkt_manager_thread = 0; 1233 1234 ret = kthread_add(&siftr_pkt_manager_thread, NULL, NULL, 1235 &siftr_pkt_manager_thr, RFNOWAIT, 0, 1236 "siftr_pkt_manager_thr"); 1237 1238 siftr_pfil(HOOK); 1239 1240 microtime(&tval); 1241 1242 sbuf_printf(s, 1243 "enable_time_secs=%jd\tenable_time_usecs=%06ld\t" 1244 "siftrver=%s\thz=%u\ttcp_rtt_scale=%u\tsysname=%s\t" 1245 "sysver=%u\tipmode=%u\n", 1246 (intmax_t)tval.tv_sec, tval.tv_usec, MODVERSION_STR, hz, 1247 TCP_RTT_SCALE, SYS_NAME, __FreeBSD_version, SIFTR_IPMODE); 1248 1249 sbuf_finish(s); 1250 alq_writen(siftr_alq, sbuf_data(s), sbuf_len(s), ALQ_WAITOK); 1251 1252 } else if (action == SIFTR_DISABLE && siftr_pkt_manager_thr != NULL) { 1253 /* 1254 * Remove the pfil hook functions. All threads currently in 1255 * the hook functions are allowed to exit before siftr_pfil() 1256 * returns. 1257 */ 1258 siftr_pfil(UNHOOK); 1259 1260 /* This will block until the pkt manager thread unlocks it. */ 1261 mtx_lock(&siftr_pkt_mgr_mtx); 1262 1263 /* Tell the pkt manager thread that it should exit now. */ 1264 siftr_exit_pkt_manager_thread = 1; 1265 1266 /* 1267 * Wake the pkt_manager thread so it realises that 1268 * siftr_exit_pkt_manager_thread == 1 and exits gracefully. 1269 * The wakeup won't be delivered until we unlock 1270 * siftr_pkt_mgr_mtx so this isn't racy. 1271 */ 1272 wakeup(&wait_for_pkt); 1273 1274 /* Wait for the pkt_manager thread to exit. */ 1275 mtx_sleep(siftr_pkt_manager_thr, &siftr_pkt_mgr_mtx, PWAIT, 1276 "thrwait", 0); 1277 1278 siftr_pkt_manager_thr = NULL; 1279 mtx_unlock(&siftr_pkt_mgr_mtx); 1280 1281 totalss.n_in = DPCPU_VARSUM(ss, n_in); 1282 totalss.n_out = DPCPU_VARSUM(ss, n_out); 1283 totalss.nskip_in_malloc = DPCPU_VARSUM(ss, nskip_in_malloc); 1284 totalss.nskip_out_malloc = DPCPU_VARSUM(ss, nskip_out_malloc); 1285 totalss.nskip_in_mtx = DPCPU_VARSUM(ss, nskip_in_mtx); 1286 totalss.nskip_out_mtx = DPCPU_VARSUM(ss, nskip_out_mtx); 1287 totalss.nskip_in_tcpcb = DPCPU_VARSUM(ss, nskip_in_tcpcb); 1288 totalss.nskip_out_tcpcb = DPCPU_VARSUM(ss, nskip_out_tcpcb); 1289 totalss.nskip_in_inpcb = DPCPU_VARSUM(ss, nskip_in_inpcb); 1290 totalss.nskip_out_inpcb = DPCPU_VARSUM(ss, nskip_out_inpcb); 1291 1292 total_skipped_pkts = totalss.nskip_in_malloc + 1293 totalss.nskip_out_malloc + totalss.nskip_in_mtx + 1294 totalss.nskip_out_mtx + totalss.nskip_in_tcpcb + 1295 totalss.nskip_out_tcpcb + totalss.nskip_in_inpcb + 1296 totalss.nskip_out_inpcb; 1297 1298 microtime(&tval); 1299 1300 sbuf_printf(s, 1301 "disable_time_secs=%jd\tdisable_time_usecs=%06ld\t" 1302 "num_inbound_tcp_pkts=%ju\tnum_outbound_tcp_pkts=%ju\t" 1303 "total_tcp_pkts=%ju\tnum_inbound_skipped_pkts_malloc=%u\t" 1304 "num_outbound_skipped_pkts_malloc=%u\t" 1305 "num_inbound_skipped_pkts_mtx=%u\t" 1306 "num_outbound_skipped_pkts_mtx=%u\t" 1307 "num_inbound_skipped_pkts_tcpcb=%u\t" 1308 "num_outbound_skipped_pkts_tcpcb=%u\t" 1309 "num_inbound_skipped_pkts_inpcb=%u\t" 1310 "num_outbound_skipped_pkts_inpcb=%u\t" 1311 "total_skipped_tcp_pkts=%u\tflow_list=", 1312 (intmax_t)tval.tv_sec, 1313 tval.tv_usec, 1314 (uintmax_t)totalss.n_in, 1315 (uintmax_t)totalss.n_out, 1316 (uintmax_t)(totalss.n_in + totalss.n_out), 1317 totalss.nskip_in_malloc, 1318 totalss.nskip_out_malloc, 1319 totalss.nskip_in_mtx, 1320 totalss.nskip_out_mtx, 1321 totalss.nskip_in_tcpcb, 1322 totalss.nskip_out_tcpcb, 1323 totalss.nskip_in_inpcb, 1324 totalss.nskip_out_inpcb, 1325 total_skipped_pkts); 1326 1327 /* 1328 * Iterate over the flow hash, printing a summary of each 1329 * flow seen and freeing any malloc'd memory. 1330 * The hash consists of an array of LISTs (man 3 queue). 1331 */ 1332 for (i = 0; i <= siftr_hashmask; i++) { 1333 LIST_FOREACH_SAFE(counter, counter_hash + i, nodes, 1334 tmp_counter) { 1335 key = counter->key; 1336 key_index = 1; 1337 1338 ipver = key[0]; 1339 1340 memcpy(laddr, key + key_index, sizeof(laddr)); 1341 key_index += sizeof(laddr); 1342 memcpy(&lport, key + key_index, sizeof(lport)); 1343 key_index += sizeof(lport); 1344 memcpy(faddr, key + key_index, sizeof(faddr)); 1345 key_index += sizeof(faddr); 1346 memcpy(&fport, key + key_index, sizeof(fport)); 1347 1348#ifdef SIFTR_IPV6 1349 laddr[3] = ntohl(laddr[3]); 1350 faddr[3] = ntohl(faddr[3]); 1351 1352 if (ipver == INP_IPV6) { 1353 laddr[0] = ntohl(laddr[0]); 1354 laddr[1] = ntohl(laddr[1]); 1355 laddr[2] = ntohl(laddr[2]); 1356 faddr[0] = ntohl(faddr[0]); 1357 faddr[1] = ntohl(faddr[1]); 1358 faddr[2] = ntohl(faddr[2]); 1359 1360 sbuf_printf(s, 1361 "%x:%x:%x:%x:%x:%x:%x:%x;%u-" 1362 "%x:%x:%x:%x:%x:%x:%x:%x;%u,", 1363 UPPER_SHORT(laddr[0]), 1364 LOWER_SHORT(laddr[0]), 1365 UPPER_SHORT(laddr[1]), 1366 LOWER_SHORT(laddr[1]), 1367 UPPER_SHORT(laddr[2]), 1368 LOWER_SHORT(laddr[2]), 1369 UPPER_SHORT(laddr[3]), 1370 LOWER_SHORT(laddr[3]), 1371 ntohs(lport), 1372 UPPER_SHORT(faddr[0]), 1373 LOWER_SHORT(faddr[0]), 1374 UPPER_SHORT(faddr[1]), 1375 LOWER_SHORT(faddr[1]), 1376 UPPER_SHORT(faddr[2]), 1377 LOWER_SHORT(faddr[2]), 1378 UPPER_SHORT(faddr[3]), 1379 LOWER_SHORT(faddr[3]), 1380 ntohs(fport)); 1381 } else { 1382 laddr[0] = FIRST_OCTET(laddr[3]); 1383 laddr[1] = SECOND_OCTET(laddr[3]); 1384 laddr[2] = THIRD_OCTET(laddr[3]); 1385 laddr[3] = FOURTH_OCTET(laddr[3]); 1386 faddr[0] = FIRST_OCTET(faddr[3]); 1387 faddr[1] = SECOND_OCTET(faddr[3]); 1388 faddr[2] = THIRD_OCTET(faddr[3]); 1389 faddr[3] = FOURTH_OCTET(faddr[3]); 1390#endif 1391 sbuf_printf(s, 1392 "%u.%u.%u.%u;%u-%u.%u.%u.%u;%u,", 1393 laddr[0], 1394 laddr[1], 1395 laddr[2], 1396 laddr[3], 1397 ntohs(lport), 1398 faddr[0], 1399 faddr[1], 1400 faddr[2], 1401 faddr[3], 1402 ntohs(fport)); 1403#ifdef SIFTR_IPV6 1404 } 1405#endif 1406 1407 free(counter, M_SIFTR_HASHNODE); 1408 } 1409 1410 LIST_INIT(counter_hash + i); 1411 } 1412 1413 sbuf_printf(s, "\n"); 1414 sbuf_finish(s); 1415 1416 i = 0; 1417 do { 1418 bytes_to_write = min(SIFTR_ALQ_BUFLEN, sbuf_len(s)-i); 1419 alq_writen(siftr_alq, sbuf_data(s)+i, bytes_to_write, ALQ_WAITOK); 1420 i += bytes_to_write; 1421 } while (i < sbuf_len(s)); 1422 1423 alq_close(siftr_alq); 1424 siftr_alq = NULL; 1425 } else 1426 error = EINVAL; 1427 1428 sbuf_delete(s); 1429 1430 /* 1431 * XXX: Should be using ret to check if any functions fail 1432 * and set error appropriately 1433 */ 1434 1435 return (error); 1436} 1437 1438 1439static int 1440siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS) 1441{ 1442 int error; 1443 uint32_t new; 1444 1445 new = siftr_enabled; 1446 error = sysctl_handle_int(oidp, &new, 0, req); 1447 if (error == 0 && req->newptr != NULL) { 1448 if (new > 1) 1449 return (EINVAL); 1450 else if (new != siftr_enabled) { 1451 if ((error = siftr_manage_ops(new)) == 0) { 1452 siftr_enabled = new; 1453 } else { 1454 siftr_manage_ops(SIFTR_DISABLE); 1455 } 1456 } 1457 } 1458 1459 return (error); 1460} 1461 1462 1463static void 1464siftr_shutdown_handler(void *arg) 1465{ 1466 if (siftr_enabled == 1) { 1467 siftr_manage_ops(SIFTR_DISABLE); 1468 } 1469} 1470 1471 1472/* 1473 * Module is being unloaded or machine is shutting down. Take care of cleanup. 1474 */ 1475static int 1476deinit_siftr(void) 1477{ 1478 /* Cleanup. */ 1479 siftr_manage_ops(SIFTR_DISABLE); 1480 hashdestroy(counter_hash, M_SIFTR, siftr_hashmask); 1481 mtx_destroy(&siftr_pkt_queue_mtx); 1482 mtx_destroy(&siftr_pkt_mgr_mtx); 1483 1484 return (0); 1485} 1486 1487 1488/* 1489 * Module has just been loaded into the kernel. 1490 */ 1491static int 1492init_siftr(void) 1493{ 1494 EVENTHANDLER_REGISTER(shutdown_pre_sync, siftr_shutdown_handler, NULL, 1495 SHUTDOWN_PRI_FIRST); 1496 1497 /* Initialise our flow counter hash table. */ 1498 counter_hash = hashinit(SIFTR_EXPECTED_MAX_TCP_FLOWS, M_SIFTR, 1499 &siftr_hashmask); 1500 1501 mtx_init(&siftr_pkt_queue_mtx, "siftr_pkt_queue_mtx", NULL, MTX_DEF); 1502 mtx_init(&siftr_pkt_mgr_mtx, "siftr_pkt_mgr_mtx", NULL, MTX_DEF); 1503 1504 /* Print message to the user's current terminal. */ 1505 uprintf("\nStatistical Information For TCP Research (SIFTR) %s\n" 1506 " http://caia.swin.edu.au/urp/newtcp\n\n", 1507 MODVERSION_STR); 1508 1509 return (0); 1510} 1511 1512 1513/* 1514 * This is the function that is called to load and unload the module. 1515 * When the module is loaded, this function is called once with 1516 * "what" == MOD_LOAD 1517 * When the module is unloaded, this function is called twice with 1518 * "what" = MOD_QUIESCE first, followed by "what" = MOD_UNLOAD second 1519 * When the system is shut down e.g. CTRL-ALT-DEL or using the shutdown command, 1520 * this function is called once with "what" = MOD_SHUTDOWN 1521 * When the system is shut down, the handler isn't called until the very end 1522 * of the shutdown sequence i.e. after the disks have been synced. 1523 */ 1524static int 1525siftr_load_handler(module_t mod, int what, void *arg) 1526{ 1527 int ret; 1528 1529 switch (what) { 1530 case MOD_LOAD: 1531 ret = init_siftr(); 1532 break; 1533 1534 case MOD_QUIESCE: 1535 case MOD_SHUTDOWN: 1536 ret = deinit_siftr(); 1537 break; 1538 1539 case MOD_UNLOAD: 1540 ret = 0; 1541 break; 1542 1543 default: 1544 ret = EINVAL; 1545 break; 1546 } 1547 1548 return (ret); 1549} 1550 1551 1552static moduledata_t siftr_mod = { 1553 .name = "siftr", 1554 .evhand = siftr_load_handler, 1555}; 1556 1557/* 1558 * Param 1: name of the kernel module 1559 * Param 2: moduledata_t struct containing info about the kernel module 1560 * and the execution entry point for the module 1561 * Param 3: From sysinit_sub_id enumeration in /usr/include/sys/kernel.h 1562 * Defines the module initialisation order 1563 * Param 4: From sysinit_elem_order enumeration in /usr/include/sys/kernel.h 1564 * Defines the initialisation order of this kld relative to others 1565 * within the same subsystem as defined by param 3 1566 */ 1567DECLARE_MODULE(siftr, siftr_mod, SI_SUB_LAST, SI_ORDER_ANY); 1568MODULE_DEPEND(siftr, alq, 1, 1, 1); 1569MODULE_VERSION(siftr, MODVERSION); 1570