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