1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2007-2009 5 * Swinburne University of Technology, Melbourne, Australia. 6 * Copyright (c) 2009-2010, The FreeBSD Foundation 7 * All rights reserved. 8 * 9 * Portions of this software were developed at the Centre for Advanced 10 * Internet Architectures, Swinburne University of Technology, Melbourne, 11 * Australia by Lawrence Stewart under sponsorship from the FreeBSD Foundation. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 /****************************************************** 36 * Statistical Information For TCP Research (SIFTR) 37 * 38 * A FreeBSD kernel module that adds very basic intrumentation to the 39 * TCP stack, allowing internal stats to be recorded to a log file 40 * for experimental, debugging and performance analysis purposes. 41 * 42 * SIFTR was first released in 2007 by James Healy and Lawrence Stewart whilst 43 * working on the NewTCP research project at Swinburne University of 44 * Technology's Centre for Advanced Internet Architectures, Melbourne, 45 * Australia, which was made possible in part by a grant from the Cisco 46 * University Research Program Fund at Community Foundation Silicon Valley. 47 * More details are available at: 48 * http://caia.swin.edu.au/urp/newtcp/ 49 * 50 * Work on SIFTR v1.2.x was sponsored by the FreeBSD Foundation as part of 51 * the "Enhancing the FreeBSD TCP Implementation" project 2008-2009. 52 * More details are available at: 53 * http://www.freebsdfoundation.org/ 54 * http://caia.swin.edu.au/freebsd/etcp09/ 55 * 56 * Lawrence Stewart is the current maintainer, and all contact regarding 57 * SIFTR should be directed to him via email: lastewart@swin.edu.au 58 * 59 * Initial release date: June 2007 60 * Most recent update: September 2010 61 ******************************************************/ 62 63 #include <sys/param.h> 64 #include <sys/alq.h> 65 #include <sys/errno.h> 66 #include <sys/eventhandler.h> 67 #include <sys/hash.h> 68 #include <sys/kernel.h> 69 #include <sys/kthread.h> 70 #include <sys/lock.h> 71 #include <sys/mbuf.h> 72 #include <sys/module.h> 73 #include <sys/mutex.h> 74 #include <sys/pcpu.h> 75 #include <sys/proc.h> 76 #include <sys/reboot.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 #include <net/route.h> 89 90 #include <netinet/in.h> 91 #include <netinet/in_kdtrace.h> 92 #include <netinet/in_fib.h> 93 #include <netinet/in_pcb.h> 94 #include <netinet/in_systm.h> 95 #include <netinet/in_var.h> 96 #include <netinet/ip.h> 97 #include <netinet/ip_var.h> 98 #include <netinet/tcp_var.h> 99 100 #ifdef SIFTR_IPV6 101 #include <netinet/ip6.h> 102 #include <netinet6/ip6_var.h> 103 #include <netinet6/in6_fib.h> 104 #include <netinet6/in6_pcb.h> 105 #endif /* SIFTR_IPV6 */ 106 107 #include <machine/in_cksum.h> 108 109 /* 110 * Three digit version number refers to X.Y.Z where: 111 * X is the major version number 112 * Y is bumped to mark backwards incompatible changes 113 * Z is bumped to mark backwards compatible changes 114 */ 115 #define V_MAJOR 1 116 #define V_BACKBREAK 3 117 #define V_BACKCOMPAT 0 118 #define MODVERSION __CONCAT(V_MAJOR, __CONCAT(V_BACKBREAK, V_BACKCOMPAT)) 119 #define MODVERSION_STR __XSTRING(V_MAJOR) "." __XSTRING(V_BACKBREAK) "." \ 120 __XSTRING(V_BACKCOMPAT) 121 122 #define HOOK 0 123 #define UNHOOK 1 124 #define SIFTR_EXPECTED_MAX_TCP_FLOWS 65536 125 #define SYS_NAME "FreeBSD" 126 #define PACKET_TAG_SIFTR 100 127 #define PACKET_COOKIE_SIFTR 21749576 128 #define SIFTR_LOG_FILE_MODE 0644 129 #define SIFTR_DISABLE 0 130 #define SIFTR_ENABLE 1 131 132 /* 133 * Hard upper limit on the length of log messages. Bump this up if you add new 134 * data fields such that the line length could exceed the below value. 135 */ 136 #define MAX_LOG_MSG_LEN 300 137 #define MAX_LOG_BATCH_SIZE 3 138 /* XXX: Make this a sysctl tunable. */ 139 #define SIFTR_ALQ_BUFLEN (1000*MAX_LOG_MSG_LEN) 140 141 #ifdef SIFTR_IPV6 142 #define SIFTR_IPMODE 6 143 #else 144 #define SIFTR_IPMODE 4 145 #endif 146 147 static MALLOC_DEFINE(M_SIFTR, "siftr", "dynamic memory used by SIFTR"); 148 static MALLOC_DEFINE(M_SIFTR_PKTNODE, "siftr_pktnode", 149 "SIFTR pkt_node struct"); 150 static MALLOC_DEFINE(M_SIFTR_HASHNODE, "siftr_hashnode", 151 "SIFTR flow_hash_node struct"); 152 153 /* Used as links in the pkt manager queue. */ 154 struct pkt_node { 155 /* Timestamp of pkt as noted in the pfil hook. */ 156 struct timeval tval; 157 /* Direction pkt is travelling. */ 158 enum { 159 DIR_IN = 0, 160 DIR_OUT = 1, 161 } direction; 162 /* IP version pkt_node relates to; either INP_IPV4 or INP_IPV6. */ 163 uint8_t ipver; 164 /* Local TCP port. */ 165 uint16_t lport; 166 /* Foreign TCP port. */ 167 uint16_t fport; 168 /* Local address. */ 169 union in_dependaddr laddr; 170 /* Foreign address. */ 171 union in_dependaddr faddr; 172 /* Congestion Window (bytes). */ 173 uint32_t snd_cwnd; 174 /* Sending Window (bytes). */ 175 uint32_t snd_wnd; 176 /* Receive Window (bytes). */ 177 uint32_t rcv_wnd; 178 /* More tcpcb flags storage */ 179 uint32_t t_flags2; 180 /* Slow Start Threshold (bytes). */ 181 uint32_t snd_ssthresh; 182 /* Current state of the TCP FSM. */ 183 int conn_state; 184 /* Max Segment Size (bytes). */ 185 uint32_t mss; 186 /* Smoothed RTT (usecs). */ 187 uint32_t srtt; 188 /* Is SACK enabled? */ 189 u_char sack_enabled; 190 /* Window scaling for snd window. */ 191 u_char snd_scale; 192 /* Window scaling for recv window. */ 193 u_char rcv_scale; 194 /* TCP control block flags. */ 195 u_int t_flags; 196 /* Retransmission timeout (usec). */ 197 uint32_t rto; 198 /* Size of the TCP send buffer in bytes. */ 199 u_int snd_buf_hiwater; 200 /* Current num bytes in the send socket buffer. */ 201 u_int snd_buf_cc; 202 /* Size of the TCP receive buffer in bytes. */ 203 u_int rcv_buf_hiwater; 204 /* Current num bytes in the receive socket buffer. */ 205 u_int rcv_buf_cc; 206 /* Number of bytes inflight that we are waiting on ACKs for. */ 207 u_int sent_inflight_bytes; 208 /* Number of segments currently in the reassembly queue. */ 209 int t_segqlen; 210 /* Flowid for the connection. */ 211 u_int flowid; 212 /* Flow type for the connection. */ 213 u_int flowtype; 214 /* Link to next pkt_node in the list. */ 215 STAILQ_ENTRY(pkt_node) nodes; 216 }; 217 218 struct flow_info 219 { 220 #ifdef SIFTR_IPV6 221 char laddr[INET6_ADDRSTRLEN]; /* local IP address */ 222 char faddr[INET6_ADDRSTRLEN]; /* foreign IP address */ 223 #else 224 char laddr[INET_ADDRSTRLEN]; /* local IP address */ 225 char faddr[INET_ADDRSTRLEN]; /* foreign IP address */ 226 #endif 227 uint16_t lport; /* local TCP port */ 228 uint16_t fport; /* foreign TCP port */ 229 uint32_t key; /* flowid of the connection */ 230 }; 231 232 struct flow_hash_node 233 { 234 uint16_t counter; 235 struct flow_info const_info; /* constant connection info */ 236 LIST_ENTRY(flow_hash_node) nodes; 237 }; 238 239 struct siftr_stats 240 { 241 /* # TCP pkts seen by the SIFTR PFIL hooks, including any skipped. */ 242 uint64_t n_in; 243 uint64_t n_out; 244 /* # pkts skipped due to failed malloc calls. */ 245 uint32_t nskip_in_malloc; 246 uint32_t nskip_out_malloc; 247 /* # pkts skipped due to failed inpcb lookups. */ 248 uint32_t nskip_in_inpcb; 249 uint32_t nskip_out_inpcb; 250 /* # pkts skipped due to failed tcpcb lookups. */ 251 uint32_t nskip_in_tcpcb; 252 uint32_t nskip_out_tcpcb; 253 /* # pkts skipped due to stack reinjection. */ 254 uint32_t nskip_in_dejavu; 255 uint32_t nskip_out_dejavu; 256 }; 257 258 DPCPU_DEFINE_STATIC(struct siftr_stats, ss); 259 260 static volatile unsigned int siftr_exit_pkt_manager_thread = 0; 261 static unsigned int siftr_enabled = 0; 262 static unsigned int siftr_pkts_per_log = 1; 263 static uint16_t siftr_port_filter = 0; 264 /* static unsigned int siftr_binary_log = 0; */ 265 static char siftr_logfile[PATH_MAX] = "/var/log/siftr.log"; 266 static char siftr_logfile_shadow[PATH_MAX] = "/var/log/siftr.log"; 267 static u_long siftr_hashmask; 268 STAILQ_HEAD(pkthead, pkt_node) pkt_queue = STAILQ_HEAD_INITIALIZER(pkt_queue); 269 LIST_HEAD(listhead, flow_hash_node) *counter_hash; 270 static int wait_for_pkt; 271 static struct alq *siftr_alq = NULL; 272 static struct mtx siftr_pkt_queue_mtx; 273 static struct mtx siftr_pkt_mgr_mtx; 274 static struct thread *siftr_pkt_manager_thr = NULL; 275 static char direction[2] = {'i','o'}; 276 static eventhandler_tag siftr_shutdown_tag; 277 278 /* Required function prototypes. */ 279 static int siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS); 280 static int siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS); 281 282 /* Declare the net.inet.siftr sysctl tree and populate it. */ 283 284 SYSCTL_DECL(_net_inet_siftr); 285 286 SYSCTL_NODE(_net_inet, OID_AUTO, siftr, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL, 287 "siftr related settings"); 288 289 SYSCTL_PROC(_net_inet_siftr, OID_AUTO, enabled, 290 CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 291 &siftr_enabled, 0, &siftr_sysctl_enabled_handler, "IU", 292 "switch siftr module operations on/off"); 293 294 SYSCTL_PROC(_net_inet_siftr, OID_AUTO, logfile, 295 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &siftr_logfile_shadow, 296 sizeof(siftr_logfile_shadow), &siftr_sysctl_logfile_name_handler, "A", 297 "file to save siftr log messages to"); 298 299 SYSCTL_UINT(_net_inet_siftr, OID_AUTO, ppl, CTLFLAG_RW, 300 &siftr_pkts_per_log, 1, 301 "number of packets between generating a log message"); 302 303 SYSCTL_U16(_net_inet_siftr, OID_AUTO, port_filter, CTLFLAG_RW, 304 &siftr_port_filter, 0, 305 "enable packet filter on a TCP port"); 306 307 /* XXX: TODO 308 SYSCTL_UINT(_net_inet_siftr, OID_AUTO, binary, CTLFLAG_RW, 309 &siftr_binary_log, 0, 310 "write log files in binary instead of ascii"); 311 */ 312 313 /* Begin functions. */ 314 315 static inline struct flow_hash_node * 316 siftr_find_flow(struct listhead *counter_list, uint32_t id) 317 { 318 struct flow_hash_node *hash_node; 319 /* 320 * If the list is not empty i.e. the hash index has 321 * been used by another flow previously. 322 */ 323 if (LIST_FIRST(counter_list) != NULL) { 324 /* 325 * Loop through the hash nodes in the list. 326 * There should normally only be 1 hash node in the list. 327 */ 328 LIST_FOREACH(hash_node, counter_list, nodes) { 329 /* 330 * Check if the key for the pkt we are currently 331 * processing is the same as the key stored in the 332 * hash node we are currently processing. 333 * If they are the same, then we've found the 334 * hash node that stores the counter for the flow 335 * the pkt belongs to. 336 */ 337 if (hash_node->const_info.key == id) { 338 return hash_node; 339 } 340 } 341 } 342 343 return NULL; 344 } 345 346 static inline struct flow_hash_node * 347 siftr_new_hash_node(struct flow_info info, int dir, 348 struct siftr_stats *ss) 349 { 350 struct flow_hash_node *hash_node; 351 struct listhead *counter_list; 352 353 counter_list = counter_hash + (info.key & siftr_hashmask); 354 /* Create a new hash node to store the flow's constant info. */ 355 hash_node = malloc(sizeof(struct flow_hash_node), M_SIFTR_HASHNODE, 356 M_NOWAIT|M_ZERO); 357 358 if (hash_node != NULL) { 359 /* Initialise our new hash node list entry. */ 360 hash_node->counter = 0; 361 hash_node->const_info = info; 362 LIST_INSERT_HEAD(counter_list, hash_node, nodes); 363 return hash_node; 364 } else { 365 /* malloc failed */ 366 if (dir == DIR_IN) 367 ss->nskip_in_malloc++; 368 else 369 ss->nskip_out_malloc++; 370 371 return NULL; 372 } 373 } 374 375 static int 376 siftr_process_pkt(struct pkt_node * pkt_node, char *buf) 377 { 378 struct flow_hash_node *hash_node; 379 struct listhead *counter_list; 380 int ret_sz; 381 382 if (pkt_node->flowid == 0) { 383 panic("%s: flowid not available", __func__); 384 } 385 386 counter_list = counter_hash + (pkt_node->flowid & siftr_hashmask); 387 hash_node = siftr_find_flow(counter_list, pkt_node->flowid); 388 389 if (hash_node == NULL) { 390 return 0; 391 } else if (siftr_pkts_per_log > 1) { 392 /* 393 * Taking the remainder of the counter divided 394 * by the current value of siftr_pkts_per_log 395 * and storing that in counter provides a neat 396 * way to modulate the frequency of log 397 * messages being written to the log file. 398 */ 399 hash_node->counter = (hash_node->counter + 1) % 400 siftr_pkts_per_log; 401 /* 402 * If we have not seen enough packets since the last time 403 * we wrote a log message for this connection, return. 404 */ 405 if (hash_node->counter > 0) 406 return 0; 407 } 408 409 /* Construct a log message. */ 410 ret_sz = snprintf(buf, MAX_LOG_MSG_LEN, 411 "%c,%jd.%06ld,%s,%hu,%s,%hu,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u," 412 "%u,%u,%u,%u,%u,%u,%u,%u\n", 413 direction[pkt_node->direction], 414 (intmax_t)pkt_node->tval.tv_sec, 415 pkt_node->tval.tv_usec, 416 hash_node->const_info.laddr, 417 hash_node->const_info.lport, 418 hash_node->const_info.faddr, 419 hash_node->const_info.fport, 420 pkt_node->snd_ssthresh, 421 pkt_node->snd_cwnd, 422 pkt_node->t_flags2, 423 pkt_node->snd_wnd, 424 pkt_node->rcv_wnd, 425 pkt_node->snd_scale, 426 pkt_node->rcv_scale, 427 pkt_node->conn_state, 428 pkt_node->mss, 429 pkt_node->srtt, 430 pkt_node->sack_enabled, 431 pkt_node->t_flags, 432 pkt_node->rto, 433 pkt_node->snd_buf_hiwater, 434 pkt_node->snd_buf_cc, 435 pkt_node->rcv_buf_hiwater, 436 pkt_node->rcv_buf_cc, 437 pkt_node->sent_inflight_bytes, 438 pkt_node->t_segqlen, 439 pkt_node->flowid, 440 pkt_node->flowtype); 441 442 return ret_sz; 443 } 444 445 static void 446 siftr_pkt_manager_thread(void *arg) 447 { 448 STAILQ_HEAD(pkthead, pkt_node) tmp_pkt_queue = 449 STAILQ_HEAD_INITIALIZER(tmp_pkt_queue); 450 struct pkt_node *pkt_node; 451 uint8_t draining; 452 struct ale *log_buf; 453 int ret_sz, cnt = 0; 454 char *bufp; 455 456 draining = 2; 457 458 mtx_lock(&siftr_pkt_mgr_mtx); 459 460 /* draining == 0 when queue has been flushed and it's safe to exit. */ 461 while (draining) { 462 /* 463 * Sleep until we are signalled to wake because thread has 464 * been told to exit or until 1 tick has passed. 465 */ 466 mtx_sleep(&wait_for_pkt, &siftr_pkt_mgr_mtx, PWAIT, "pktwait", 467 1); 468 469 /* Gain exclusive access to the pkt_node queue. */ 470 mtx_lock(&siftr_pkt_queue_mtx); 471 472 /* 473 * Move pkt_queue to tmp_pkt_queue, which leaves 474 * pkt_queue empty and ready to receive more pkt_nodes. 475 */ 476 STAILQ_CONCAT(&tmp_pkt_queue, &pkt_queue); 477 478 /* 479 * We've finished making changes to the list. Unlock it 480 * so the pfil hooks can continue queuing pkt_nodes. 481 */ 482 mtx_unlock(&siftr_pkt_queue_mtx); 483 484 /* 485 * We can't hold a mutex whilst calling siftr_process_pkt 486 * because ALQ might sleep waiting for buffer space. 487 */ 488 mtx_unlock(&siftr_pkt_mgr_mtx); 489 490 while ((pkt_node = STAILQ_FIRST(&tmp_pkt_queue)) != NULL) { 491 492 log_buf = alq_getn(siftr_alq, MAX_LOG_MSG_LEN * 493 ((STAILQ_NEXT(pkt_node, nodes) != NULL) ? 494 MAX_LOG_BATCH_SIZE : 1), 495 ALQ_WAITOK); 496 497 if (log_buf != NULL) { 498 log_buf->ae_bytesused = 0; 499 bufp = log_buf->ae_data; 500 } else { 501 /* 502 * Should only happen if the ALQ is shutting 503 * down. 504 */ 505 bufp = NULL; 506 } 507 508 /* Flush all pkt_nodes to the log file. */ 509 STAILQ_FOREACH(pkt_node, &tmp_pkt_queue, nodes) { 510 if (log_buf != NULL) { 511 ret_sz = siftr_process_pkt(pkt_node, 512 bufp); 513 bufp += ret_sz; 514 log_buf->ae_bytesused += ret_sz; 515 } 516 if (++cnt >= MAX_LOG_BATCH_SIZE) 517 break; 518 } 519 if (log_buf != NULL) { 520 alq_post_flags(siftr_alq, log_buf, 0); 521 } 522 for (;cnt > 0; cnt--) { 523 pkt_node = STAILQ_FIRST(&tmp_pkt_queue); 524 STAILQ_REMOVE_HEAD(&tmp_pkt_queue, nodes); 525 free(pkt_node, M_SIFTR_PKTNODE); 526 } 527 } 528 529 KASSERT(STAILQ_EMPTY(&tmp_pkt_queue), 530 ("SIFTR tmp_pkt_queue not empty after flush")); 531 532 mtx_lock(&siftr_pkt_mgr_mtx); 533 534 /* 535 * If siftr_exit_pkt_manager_thread gets set during the window 536 * where we are draining the tmp_pkt_queue above, there might 537 * still be pkts in pkt_queue that need to be drained. 538 * Allow one further iteration to occur after 539 * siftr_exit_pkt_manager_thread has been set to ensure 540 * pkt_queue is completely empty before we kill the thread. 541 * 542 * siftr_exit_pkt_manager_thread is set only after the pfil 543 * hooks have been removed, so only 1 extra iteration 544 * is needed to drain the queue. 545 */ 546 if (siftr_exit_pkt_manager_thread) 547 draining--; 548 } 549 550 mtx_unlock(&siftr_pkt_mgr_mtx); 551 552 /* Calls wakeup on this thread's struct thread ptr. */ 553 kthread_exit(); 554 } 555 556 /* 557 * Check if a given mbuf has the SIFTR mbuf tag. If it does, log the fact that 558 * it's a reinjected packet and return. If it doesn't, tag the mbuf and return. 559 * Return value >0 means the caller should skip processing this mbuf. 560 */ 561 static inline int 562 siftr_chkreinject(struct mbuf *m, int dir, struct siftr_stats *ss) 563 { 564 if (m_tag_locate(m, PACKET_COOKIE_SIFTR, PACKET_TAG_SIFTR, NULL) 565 != NULL) { 566 if (dir == PFIL_IN) 567 ss->nskip_in_dejavu++; 568 else 569 ss->nskip_out_dejavu++; 570 571 return (1); 572 } else { 573 struct m_tag *tag = m_tag_alloc(PACKET_COOKIE_SIFTR, 574 PACKET_TAG_SIFTR, 0, M_NOWAIT); 575 if (tag == NULL) { 576 if (dir == PFIL_IN) 577 ss->nskip_in_malloc++; 578 else 579 ss->nskip_out_malloc++; 580 581 return (1); 582 } 583 584 m_tag_prepend(m, tag); 585 } 586 587 return (0); 588 } 589 590 /* 591 * Look up an inpcb for a packet. Return the inpcb pointer if found, or NULL 592 * otherwise. 593 */ 594 static inline struct inpcb * 595 siftr_findinpcb(int ipver, struct ip *ip, struct mbuf *m, uint16_t sport, 596 uint16_t dport, int dir, struct siftr_stats *ss) 597 { 598 struct inpcb *inp; 599 600 /* We need the tcbinfo lock. */ 601 INP_INFO_WUNLOCK_ASSERT(&V_tcbinfo); 602 603 if (dir == PFIL_IN) 604 inp = (ipver == INP_IPV4 ? 605 in_pcblookup(&V_tcbinfo, ip->ip_src, sport, ip->ip_dst, 606 dport, INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif) 607 : 608 #ifdef SIFTR_IPV6 609 in6_pcblookup(&V_tcbinfo, 610 &((struct ip6_hdr *)ip)->ip6_src, sport, 611 &((struct ip6_hdr *)ip)->ip6_dst, dport, INPLOOKUP_RLOCKPCB, 612 m->m_pkthdr.rcvif) 613 #else 614 NULL 615 #endif 616 ); 617 618 else 619 inp = (ipver == INP_IPV4 ? 620 in_pcblookup(&V_tcbinfo, ip->ip_dst, dport, ip->ip_src, 621 sport, INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif) 622 : 623 #ifdef SIFTR_IPV6 624 in6_pcblookup(&V_tcbinfo, 625 &((struct ip6_hdr *)ip)->ip6_dst, dport, 626 &((struct ip6_hdr *)ip)->ip6_src, sport, INPLOOKUP_RLOCKPCB, 627 m->m_pkthdr.rcvif) 628 #else 629 NULL 630 #endif 631 ); 632 633 /* If we can't find the inpcb, bail. */ 634 if (inp == NULL) { 635 if (dir == PFIL_IN) 636 ss->nskip_in_inpcb++; 637 else 638 ss->nskip_out_inpcb++; 639 } 640 641 return (inp); 642 } 643 644 static inline uint32_t 645 siftr_get_flowid(struct inpcb *inp, int ipver, uint32_t *phashtype) 646 { 647 if (inp->inp_flowid == 0) { 648 #ifdef SIFTR_IPV6 649 if (ipver == INP_IPV6) { 650 return fib6_calc_packet_hash(&inp->in6p_laddr, 651 &inp->in6p_faddr, 652 inp->inp_lport, 653 inp->inp_fport, 654 IPPROTO_TCP, 655 phashtype); 656 } else 657 #endif 658 { 659 return fib4_calc_packet_hash(inp->inp_laddr, 660 inp->inp_faddr, 661 inp->inp_lport, 662 inp->inp_fport, 663 IPPROTO_TCP, 664 phashtype); 665 } 666 } else { 667 *phashtype = inp->inp_flowtype; 668 return inp->inp_flowid; 669 } 670 } 671 672 static inline void 673 siftr_siftdata(struct pkt_node *pn, struct inpcb *inp, struct tcpcb *tp, 674 int ipver, int dir, int inp_locally_locked) 675 { 676 pn->ipver = ipver; 677 pn->lport = inp->inp_lport; 678 pn->fport = inp->inp_fport; 679 pn->laddr = inp->inp_inc.inc_ie.ie_dependladdr; 680 pn->faddr = inp->inp_inc.inc_ie.ie_dependfaddr; 681 pn->snd_cwnd = tp->snd_cwnd; 682 pn->snd_wnd = tp->snd_wnd; 683 pn->rcv_wnd = tp->rcv_wnd; 684 pn->t_flags2 = tp->t_flags2; 685 pn->snd_ssthresh = tp->snd_ssthresh; 686 pn->snd_scale = tp->snd_scale; 687 pn->rcv_scale = tp->rcv_scale; 688 pn->conn_state = tp->t_state; 689 pn->mss = tp->t_maxseg; 690 pn->srtt = ((uint64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT; 691 pn->sack_enabled = (tp->t_flags & TF_SACK_PERMIT) != 0; 692 pn->t_flags = tp->t_flags; 693 pn->rto = tp->t_rxtcur * tick; 694 pn->snd_buf_hiwater = inp->inp_socket->so_snd.sb_hiwat; 695 pn->snd_buf_cc = sbused(&inp->inp_socket->so_snd); 696 pn->rcv_buf_hiwater = inp->inp_socket->so_rcv.sb_hiwat; 697 pn->rcv_buf_cc = sbused(&inp->inp_socket->so_rcv); 698 pn->sent_inflight_bytes = tp->snd_max - tp->snd_una; 699 pn->t_segqlen = tp->t_segqlen; 700 701 /* We've finished accessing the tcb so release the lock. */ 702 if (inp_locally_locked) 703 INP_RUNLOCK(inp); 704 705 pn->direction = (dir == PFIL_IN ? DIR_IN : DIR_OUT); 706 707 /* 708 * Significantly more accurate than using getmicrotime(), but slower! 709 * Gives true microsecond resolution at the expense of a hit to 710 * maximum pps throughput processing when SIFTR is loaded and enabled. 711 */ 712 microtime(&pn->tval); 713 TCP_PROBE1(siftr, pn); 714 } 715 716 /* 717 * pfil hook that is called for each IPv4 packet making its way through the 718 * stack in either direction. 719 * The pfil subsystem holds a non-sleepable mutex somewhere when 720 * calling our hook function, so we can't sleep at all. 721 * It's very important to use the M_NOWAIT flag with all function calls 722 * that support it so that they won't sleep, otherwise you get a panic. 723 */ 724 static pfil_return_t 725 siftr_chkpkt(struct mbuf **m, struct ifnet *ifp, int flags, 726 void *ruleset __unused, struct inpcb *inp) 727 { 728 struct pkt_node *pn; 729 struct ip *ip; 730 struct tcphdr *th; 731 struct tcpcb *tp; 732 struct siftr_stats *ss; 733 unsigned int ip_hl; 734 int inp_locally_locked, dir; 735 uint32_t hash_id, hash_type; 736 struct listhead *counter_list; 737 struct flow_hash_node *hash_node; 738 739 inp_locally_locked = 0; 740 dir = PFIL_DIR(flags); 741 ss = DPCPU_PTR(ss); 742 743 /* 744 * m_pullup is not required here because ip_{input|output} 745 * already do the heavy lifting for us. 746 */ 747 748 ip = mtod(*m, struct ip *); 749 750 /* Only continue processing if the packet is TCP. */ 751 if (ip->ip_p != IPPROTO_TCP) 752 goto ret; 753 754 /* 755 * Create a tcphdr struct starting at the correct offset 756 * in the IP packet. ip->ip_hl gives the ip header length 757 * in 4-byte words, so multiply it to get the size in bytes. 758 */ 759 ip_hl = (ip->ip_hl << 2); 760 th = (struct tcphdr *)((caddr_t)ip + ip_hl); 761 762 /* 763 * Only pkts selected by the tcp port filter 764 * can be inserted into the pkt_queue 765 */ 766 if ((siftr_port_filter != 0) && 767 (siftr_port_filter != ntohs(th->th_sport)) && 768 (siftr_port_filter != ntohs(th->th_dport))) { 769 goto ret; 770 } 771 772 /* 773 * If a kernel subsystem reinjects packets into the stack, our pfil 774 * hook will be called multiple times for the same packet. 775 * Make sure we only process unique packets. 776 */ 777 if (siftr_chkreinject(*m, dir, ss)) 778 goto ret; 779 780 if (dir == PFIL_IN) 781 ss->n_in++; 782 else 783 ss->n_out++; 784 785 /* 786 * If the pfil hooks don't provide a pointer to the 787 * inpcb, we need to find it ourselves and lock it. 788 */ 789 if (!inp) { 790 /* Find the corresponding inpcb for this pkt. */ 791 inp = siftr_findinpcb(INP_IPV4, ip, *m, th->th_sport, 792 th->th_dport, dir, ss); 793 794 if (inp == NULL) 795 goto ret; 796 else 797 inp_locally_locked = 1; 798 } 799 800 INP_LOCK_ASSERT(inp); 801 802 /* Find the TCP control block that corresponds with this packet */ 803 tp = intotcpcb(inp); 804 805 /* 806 * If we can't find the TCP control block (happens occasionaly for a 807 * packet sent during the shutdown phase of a TCP connection), or the 808 * TCP control block has not initialized (happens during TCPS_SYN_SENT), 809 * bail. 810 */ 811 if (tp == NULL || tp->t_state < TCPS_ESTABLISHED) { 812 if (dir == PFIL_IN) 813 ss->nskip_in_tcpcb++; 814 else 815 ss->nskip_out_tcpcb++; 816 817 goto inp_unlock; 818 } 819 820 hash_id = siftr_get_flowid(inp, INP_IPV4, &hash_type); 821 counter_list = counter_hash + (hash_id & siftr_hashmask); 822 hash_node = siftr_find_flow(counter_list, hash_id); 823 824 /* If this flow hasn't been seen before, we create a new entry. */ 825 if (hash_node == NULL) { 826 struct flow_info info; 827 828 inet_ntoa_r(inp->inp_laddr, info.laddr); 829 inet_ntoa_r(inp->inp_faddr, info.faddr); 830 info.lport = ntohs(inp->inp_lport); 831 info.fport = ntohs(inp->inp_fport); 832 info.key = hash_id; 833 834 hash_node = siftr_new_hash_node(info, dir, ss); 835 } 836 837 if (hash_node == NULL) { 838 goto inp_unlock; 839 } 840 841 pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO); 842 843 if (pn == NULL) { 844 if (dir == PFIL_IN) 845 ss->nskip_in_malloc++; 846 else 847 ss->nskip_out_malloc++; 848 849 goto inp_unlock; 850 } 851 852 pn->flowid = hash_id; 853 pn->flowtype = hash_type; 854 855 siftr_siftdata(pn, inp, tp, INP_IPV4, dir, inp_locally_locked); 856 857 mtx_lock(&siftr_pkt_queue_mtx); 858 STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes); 859 mtx_unlock(&siftr_pkt_queue_mtx); 860 goto ret; 861 862 inp_unlock: 863 if (inp_locally_locked) 864 INP_RUNLOCK(inp); 865 866 ret: 867 return (PFIL_PASS); 868 } 869 870 #ifdef SIFTR_IPV6 871 static pfil_return_t 872 siftr_chkpkt6(struct mbuf **m, struct ifnet *ifp, int flags, 873 void *ruleset __unused, struct inpcb *inp) 874 { 875 struct pkt_node *pn; 876 struct ip6_hdr *ip6; 877 struct tcphdr *th; 878 struct tcpcb *tp; 879 struct siftr_stats *ss; 880 unsigned int ip6_hl; 881 int inp_locally_locked, dir; 882 uint32_t hash_id, hash_type; 883 struct listhead *counter_list; 884 struct flow_hash_node *hash_node; 885 886 inp_locally_locked = 0; 887 dir = PFIL_DIR(flags); 888 ss = DPCPU_PTR(ss); 889 890 /* 891 * m_pullup is not required here because ip6_{input|output} 892 * already do the heavy lifting for us. 893 */ 894 895 ip6 = mtod(*m, struct ip6_hdr *); 896 897 /* 898 * Only continue processing if the packet is TCP 899 * XXX: We should follow the next header fields 900 * as shown on Pg 6 RFC 2460, but right now we'll 901 * only check pkts that have no extension headers. 902 */ 903 if (ip6->ip6_nxt != IPPROTO_TCP) 904 goto ret6; 905 906 /* 907 * Create a tcphdr struct starting at the correct offset 908 * in the ipv6 packet. 909 */ 910 ip6_hl = sizeof(struct ip6_hdr); 911 th = (struct tcphdr *)((caddr_t)ip6 + ip6_hl); 912 913 /* 914 * Only pkts selected by the tcp port filter 915 * can be inserted into the pkt_queue 916 */ 917 if ((siftr_port_filter != 0) && 918 (siftr_port_filter != ntohs(th->th_sport)) && 919 (siftr_port_filter != ntohs(th->th_dport))) { 920 goto ret6; 921 } 922 923 /* 924 * If a kernel subsystem reinjects packets into the stack, our pfil 925 * hook will be called multiple times for the same packet. 926 * Make sure we only process unique packets. 927 */ 928 if (siftr_chkreinject(*m, dir, ss)) 929 goto ret6; 930 931 if (dir == PFIL_IN) 932 ss->n_in++; 933 else 934 ss->n_out++; 935 936 /* 937 * For inbound packets, the pfil hooks don't provide a pointer to the 938 * inpcb, so we need to find it ourselves and lock it. 939 */ 940 if (!inp) { 941 /* Find the corresponding inpcb for this pkt. */ 942 inp = siftr_findinpcb(INP_IPV6, (struct ip *)ip6, *m, 943 th->th_sport, th->th_dport, dir, ss); 944 945 if (inp == NULL) 946 goto ret6; 947 else 948 inp_locally_locked = 1; 949 } 950 951 /* Find the TCP control block that corresponds with this packet. */ 952 tp = intotcpcb(inp); 953 954 /* 955 * If we can't find the TCP control block (happens occasionaly for a 956 * packet sent during the shutdown phase of a TCP connection), or the 957 * TCP control block has not initialized (happens during TCPS_SYN_SENT), 958 * bail. 959 */ 960 if (tp == NULL || tp->t_state < TCPS_ESTABLISHED) { 961 if (dir == PFIL_IN) 962 ss->nskip_in_tcpcb++; 963 else 964 ss->nskip_out_tcpcb++; 965 966 goto inp_unlock6; 967 } 968 969 hash_id = siftr_get_flowid(inp, INP_IPV6, &hash_type); 970 counter_list = counter_hash + (hash_id & siftr_hashmask); 971 hash_node = siftr_find_flow(counter_list, hash_id); 972 973 /* If this flow hasn't been seen before, we create a new entry. */ 974 if (!hash_node) { 975 struct flow_info info; 976 977 ip6_sprintf(info.laddr, &inp->in6p_laddr); 978 ip6_sprintf(info.faddr, &inp->in6p_faddr); 979 info.lport = ntohs(inp->inp_lport); 980 info.fport = ntohs(inp->inp_fport); 981 info.key = hash_id; 982 983 hash_node = siftr_new_hash_node(info, dir, ss); 984 } 985 986 if (!hash_node) { 987 goto inp_unlock6; 988 } 989 990 pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO); 991 992 if (pn == NULL) { 993 if (dir == PFIL_IN) 994 ss->nskip_in_malloc++; 995 else 996 ss->nskip_out_malloc++; 997 998 goto inp_unlock6; 999 } 1000 1001 pn->flowid = hash_id; 1002 pn->flowtype = hash_type; 1003 1004 siftr_siftdata(pn, inp, tp, INP_IPV6, dir, inp_locally_locked); 1005 1006 mtx_lock(&siftr_pkt_queue_mtx); 1007 STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes); 1008 mtx_unlock(&siftr_pkt_queue_mtx); 1009 goto ret6; 1010 1011 inp_unlock6: 1012 if (inp_locally_locked) 1013 INP_RUNLOCK(inp); 1014 1015 ret6: 1016 return (PFIL_PASS); 1017 } 1018 #endif /* #ifdef SIFTR_IPV6 */ 1019 1020 VNET_DEFINE_STATIC(pfil_hook_t, siftr_inet_hook); 1021 #define V_siftr_inet_hook VNET(siftr_inet_hook) 1022 #ifdef SIFTR_IPV6 1023 VNET_DEFINE_STATIC(pfil_hook_t, siftr_inet6_hook); 1024 #define V_siftr_inet6_hook VNET(siftr_inet6_hook) 1025 #endif 1026 static int 1027 siftr_pfil(int action) 1028 { 1029 struct pfil_hook_args pha = { 1030 .pa_version = PFIL_VERSION, 1031 .pa_flags = PFIL_IN | PFIL_OUT, 1032 .pa_modname = "siftr", 1033 .pa_rulname = "default", 1034 }; 1035 struct pfil_link_args pla = { 1036 .pa_version = PFIL_VERSION, 1037 .pa_flags = PFIL_IN | PFIL_OUT | PFIL_HEADPTR | PFIL_HOOKPTR, 1038 }; 1039 1040 VNET_ITERATOR_DECL(vnet_iter); 1041 1042 VNET_LIST_RLOCK(); 1043 VNET_FOREACH(vnet_iter) { 1044 CURVNET_SET(vnet_iter); 1045 1046 if (action == HOOK) { 1047 pha.pa_mbuf_chk = siftr_chkpkt; 1048 pha.pa_type = PFIL_TYPE_IP4; 1049 V_siftr_inet_hook = pfil_add_hook(&pha); 1050 pla.pa_hook = V_siftr_inet_hook; 1051 pla.pa_head = V_inet_pfil_head; 1052 (void)pfil_link(&pla); 1053 #ifdef SIFTR_IPV6 1054 pha.pa_mbuf_chk = siftr_chkpkt6; 1055 pha.pa_type = PFIL_TYPE_IP6; 1056 V_siftr_inet6_hook = pfil_add_hook(&pha); 1057 pla.pa_hook = V_siftr_inet6_hook; 1058 pla.pa_head = V_inet6_pfil_head; 1059 (void)pfil_link(&pla); 1060 #endif 1061 } else if (action == UNHOOK) { 1062 pfil_remove_hook(V_siftr_inet_hook); 1063 #ifdef SIFTR_IPV6 1064 pfil_remove_hook(V_siftr_inet6_hook); 1065 #endif 1066 } 1067 CURVNET_RESTORE(); 1068 } 1069 VNET_LIST_RUNLOCK(); 1070 1071 return (0); 1072 } 1073 1074 static int 1075 siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS) 1076 { 1077 struct alq *new_alq; 1078 int error; 1079 1080 error = sysctl_handle_string(oidp, arg1, arg2, req); 1081 1082 /* Check for error or same filename */ 1083 if (error != 0 || req->newptr == NULL || 1084 strncmp(siftr_logfile, arg1, arg2) == 0) 1085 goto done; 1086 1087 /* file name changed */ 1088 error = alq_open(&new_alq, arg1, curthread->td_ucred, 1089 SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0); 1090 if (error != 0) 1091 goto done; 1092 1093 /* 1094 * If disabled, siftr_alq == NULL so we simply close 1095 * the alq as we've proved it can be opened. 1096 * If enabled, close the existing alq and switch the old 1097 * for the new. 1098 */ 1099 if (siftr_alq == NULL) { 1100 alq_close(new_alq); 1101 } else { 1102 alq_close(siftr_alq); 1103 siftr_alq = new_alq; 1104 } 1105 1106 /* Update filename upon success */ 1107 strlcpy(siftr_logfile, arg1, arg2); 1108 done: 1109 return (error); 1110 } 1111 1112 static int 1113 siftr_manage_ops(uint8_t action) 1114 { 1115 struct siftr_stats totalss; 1116 struct timeval tval; 1117 struct flow_hash_node *counter, *tmp_counter; 1118 struct sbuf *s; 1119 int i, error; 1120 uint32_t bytes_to_write, total_skipped_pkts; 1121 1122 error = 0; 1123 total_skipped_pkts = 0; 1124 1125 /* Init an autosizing sbuf that initially holds 200 chars. */ 1126 if ((s = sbuf_new(NULL, NULL, 200, SBUF_AUTOEXTEND)) == NULL) 1127 return (-1); 1128 1129 if (action == SIFTR_ENABLE && siftr_pkt_manager_thr == NULL) { 1130 /* 1131 * Create our alq 1132 * XXX: We should abort if alq_open fails! 1133 */ 1134 alq_open(&siftr_alq, siftr_logfile, curthread->td_ucred, 1135 SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0); 1136 1137 STAILQ_INIT(&pkt_queue); 1138 1139 DPCPU_ZERO(ss); 1140 1141 siftr_exit_pkt_manager_thread = 0; 1142 1143 kthread_add(&siftr_pkt_manager_thread, NULL, NULL, 1144 &siftr_pkt_manager_thr, RFNOWAIT, 0, 1145 "siftr_pkt_manager_thr"); 1146 1147 siftr_pfil(HOOK); 1148 1149 microtime(&tval); 1150 1151 sbuf_printf(s, 1152 "enable_time_secs=%jd\tenable_time_usecs=%06ld\t" 1153 "siftrver=%s\tsysname=%s\tsysver=%u\tipmode=%u\n", 1154 (intmax_t)tval.tv_sec, tval.tv_usec, MODVERSION_STR, 1155 SYS_NAME, __FreeBSD_version, SIFTR_IPMODE); 1156 1157 sbuf_finish(s); 1158 alq_writen(siftr_alq, sbuf_data(s), sbuf_len(s), ALQ_WAITOK); 1159 1160 } else if (action == SIFTR_DISABLE && siftr_pkt_manager_thr != NULL) { 1161 /* 1162 * Remove the pfil hook functions. All threads currently in 1163 * the hook functions are allowed to exit before siftr_pfil() 1164 * returns. 1165 */ 1166 siftr_pfil(UNHOOK); 1167 1168 /* This will block until the pkt manager thread unlocks it. */ 1169 mtx_lock(&siftr_pkt_mgr_mtx); 1170 1171 /* Tell the pkt manager thread that it should exit now. */ 1172 siftr_exit_pkt_manager_thread = 1; 1173 1174 /* 1175 * Wake the pkt_manager thread so it realises that 1176 * siftr_exit_pkt_manager_thread == 1 and exits gracefully. 1177 * The wakeup won't be delivered until we unlock 1178 * siftr_pkt_mgr_mtx so this isn't racy. 1179 */ 1180 wakeup(&wait_for_pkt); 1181 1182 /* Wait for the pkt_manager thread to exit. */ 1183 mtx_sleep(siftr_pkt_manager_thr, &siftr_pkt_mgr_mtx, PWAIT, 1184 "thrwait", 0); 1185 1186 siftr_pkt_manager_thr = NULL; 1187 mtx_unlock(&siftr_pkt_mgr_mtx); 1188 1189 totalss.n_in = DPCPU_VARSUM(ss, n_in); 1190 totalss.n_out = DPCPU_VARSUM(ss, n_out); 1191 totalss.nskip_in_malloc = DPCPU_VARSUM(ss, nskip_in_malloc); 1192 totalss.nskip_out_malloc = DPCPU_VARSUM(ss, nskip_out_malloc); 1193 totalss.nskip_in_tcpcb = DPCPU_VARSUM(ss, nskip_in_tcpcb); 1194 totalss.nskip_out_tcpcb = DPCPU_VARSUM(ss, nskip_out_tcpcb); 1195 totalss.nskip_in_inpcb = DPCPU_VARSUM(ss, nskip_in_inpcb); 1196 totalss.nskip_out_inpcb = DPCPU_VARSUM(ss, nskip_out_inpcb); 1197 1198 total_skipped_pkts = totalss.nskip_in_malloc + 1199 totalss.nskip_out_malloc + totalss.nskip_in_tcpcb + 1200 totalss.nskip_out_tcpcb + totalss.nskip_in_inpcb + 1201 totalss.nskip_out_inpcb; 1202 1203 microtime(&tval); 1204 1205 sbuf_printf(s, 1206 "disable_time_secs=%jd\tdisable_time_usecs=%06ld\t" 1207 "num_inbound_tcp_pkts=%ju\tnum_outbound_tcp_pkts=%ju\t" 1208 "total_tcp_pkts=%ju\tnum_inbound_skipped_pkts_malloc=%u\t" 1209 "num_outbound_skipped_pkts_malloc=%u\t" 1210 "num_inbound_skipped_pkts_tcpcb=%u\t" 1211 "num_outbound_skipped_pkts_tcpcb=%u\t" 1212 "num_inbound_skipped_pkts_inpcb=%u\t" 1213 "num_outbound_skipped_pkts_inpcb=%u\t" 1214 "total_skipped_tcp_pkts=%u\tflow_list=", 1215 (intmax_t)tval.tv_sec, 1216 tval.tv_usec, 1217 (uintmax_t)totalss.n_in, 1218 (uintmax_t)totalss.n_out, 1219 (uintmax_t)(totalss.n_in + totalss.n_out), 1220 totalss.nskip_in_malloc, 1221 totalss.nskip_out_malloc, 1222 totalss.nskip_in_tcpcb, 1223 totalss.nskip_out_tcpcb, 1224 totalss.nskip_in_inpcb, 1225 totalss.nskip_out_inpcb, 1226 total_skipped_pkts); 1227 1228 /* 1229 * Iterate over the flow hash, printing a summary of each 1230 * flow seen and freeing any malloc'd memory. 1231 * The hash consists of an array of LISTs (man 3 queue). 1232 */ 1233 for (i = 0; i <= siftr_hashmask; i++) { 1234 LIST_FOREACH_SAFE(counter, counter_hash + i, nodes, 1235 tmp_counter) { 1236 sbuf_printf(s, "%s;%hu-%s;%hu,", 1237 counter->const_info.laddr, 1238 counter->const_info.lport, 1239 counter->const_info.faddr, 1240 counter->const_info.fport); 1241 1242 free(counter, M_SIFTR_HASHNODE); 1243 } 1244 1245 LIST_INIT(counter_hash + i); 1246 } 1247 1248 sbuf_printf(s, "\n"); 1249 sbuf_finish(s); 1250 1251 i = 0; 1252 do { 1253 bytes_to_write = min(SIFTR_ALQ_BUFLEN, sbuf_len(s)-i); 1254 alq_writen(siftr_alq, sbuf_data(s)+i, bytes_to_write, ALQ_WAITOK); 1255 i += bytes_to_write; 1256 } while (i < sbuf_len(s)); 1257 1258 alq_close(siftr_alq); 1259 siftr_alq = NULL; 1260 } else 1261 error = EINVAL; 1262 1263 sbuf_delete(s); 1264 1265 /* 1266 * XXX: Should be using ret to check if any functions fail 1267 * and set error appropriately 1268 */ 1269 1270 return (error); 1271 } 1272 1273 static int 1274 siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS) 1275 { 1276 int error; 1277 uint32_t new; 1278 1279 new = siftr_enabled; 1280 error = sysctl_handle_int(oidp, &new, 0, req); 1281 if (error == 0 && req->newptr != NULL) { 1282 if (new > 1) 1283 return (EINVAL); 1284 else if (new != siftr_enabled) { 1285 if ((error = siftr_manage_ops(new)) == 0) { 1286 siftr_enabled = new; 1287 } else { 1288 siftr_manage_ops(SIFTR_DISABLE); 1289 } 1290 } 1291 } 1292 1293 return (error); 1294 } 1295 1296 static void 1297 siftr_shutdown_handler(void *arg, int howto) 1298 { 1299 if ((howto & RB_NOSYNC) != 0 || SCHEDULER_STOPPED()) 1300 return; 1301 1302 if (siftr_enabled == 1) { 1303 siftr_manage_ops(SIFTR_DISABLE); 1304 } 1305 } 1306 1307 /* 1308 * Module is being unloaded or machine is shutting down. Take care of cleanup. 1309 */ 1310 static int 1311 deinit_siftr(void) 1312 { 1313 /* Cleanup. */ 1314 EVENTHANDLER_DEREGISTER(shutdown_pre_sync, siftr_shutdown_tag); 1315 siftr_manage_ops(SIFTR_DISABLE); 1316 hashdestroy(counter_hash, M_SIFTR, siftr_hashmask); 1317 mtx_destroy(&siftr_pkt_queue_mtx); 1318 mtx_destroy(&siftr_pkt_mgr_mtx); 1319 1320 return (0); 1321 } 1322 1323 /* 1324 * Module has just been loaded into the kernel. 1325 */ 1326 static int 1327 init_siftr(void) 1328 { 1329 siftr_shutdown_tag = EVENTHANDLER_REGISTER(shutdown_pre_sync, 1330 siftr_shutdown_handler, NULL, SHUTDOWN_PRI_FIRST); 1331 1332 /* Initialise our flow counter hash table. */ 1333 counter_hash = hashinit(SIFTR_EXPECTED_MAX_TCP_FLOWS, M_SIFTR, 1334 &siftr_hashmask); 1335 1336 mtx_init(&siftr_pkt_queue_mtx, "siftr_pkt_queue_mtx", NULL, MTX_DEF); 1337 mtx_init(&siftr_pkt_mgr_mtx, "siftr_pkt_mgr_mtx", NULL, MTX_DEF); 1338 1339 /* Print message to the user's current terminal. */ 1340 uprintf("\nStatistical Information For TCP Research (SIFTR) %s\n" 1341 " http://caia.swin.edu.au/urp/newtcp\n\n", 1342 MODVERSION_STR); 1343 1344 return (0); 1345 } 1346 1347 /* 1348 * This is the function that is called to load and unload the module. 1349 * When the module is loaded, this function is called once with 1350 * "what" == MOD_LOAD 1351 * When the module is unloaded, this function is called twice with 1352 * "what" = MOD_QUIESCE first, followed by "what" = MOD_UNLOAD second 1353 * When the system is shut down e.g. CTRL-ALT-DEL or using the shutdown command, 1354 * this function is called once with "what" = MOD_SHUTDOWN 1355 * When the system is shut down, the handler isn't called until the very end 1356 * of the shutdown sequence i.e. after the disks have been synced. 1357 */ 1358 static int 1359 siftr_load_handler(module_t mod, int what, void *arg) 1360 { 1361 int ret; 1362 1363 switch (what) { 1364 case MOD_LOAD: 1365 ret = init_siftr(); 1366 break; 1367 1368 case MOD_QUIESCE: 1369 case MOD_SHUTDOWN: 1370 ret = deinit_siftr(); 1371 break; 1372 1373 case MOD_UNLOAD: 1374 ret = 0; 1375 break; 1376 1377 default: 1378 ret = EINVAL; 1379 break; 1380 } 1381 1382 return (ret); 1383 } 1384 1385 static moduledata_t siftr_mod = { 1386 .name = "siftr", 1387 .evhand = siftr_load_handler, 1388 }; 1389 1390 /* 1391 * Param 1: name of the kernel module 1392 * Param 2: moduledata_t struct containing info about the kernel module 1393 * and the execution entry point for the module 1394 * Param 3: From sysinit_sub_id enumeration in /usr/include/sys/kernel.h 1395 * Defines the module initialisation order 1396 * Param 4: From sysinit_elem_order enumeration in /usr/include/sys/kernel.h 1397 * Defines the initialisation order of this kld relative to others 1398 * within the same subsystem as defined by param 3 1399 */ 1400 DECLARE_MODULE(siftr, siftr_mod, SI_SUB_LAST, SI_ORDER_ANY); 1401 MODULE_DEPEND(siftr, alq, 1, 1, 1); 1402 MODULE_VERSION(siftr, MODVERSION); 1403