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