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/hash.h> 68 #include <sys/kernel.h> 69 #include <sys/kthread.h> 70 #include <sys/lock.h> 71 #include <sys/mbuf.h> 72 #include <sys/module.h> 73 #include <sys/mutex.h> 74 #include <sys/pcpu.h> 75 #include <sys/proc.h> 76 #include <sys/sbuf.h> 77 #include <sys/smp.h> 78 #include <sys/socket.h> 79 #include <sys/socketvar.h> 80 #include <sys/sysctl.h> 81 #include <sys/unistd.h> 82 83 #include <net/if.h> 84 #include <net/pfil.h> 85 86 #include <netinet/in.h> 87 #include <netinet/in_pcb.h> 88 #include <netinet/in_systm.h> 89 #include <netinet/in_var.h> 90 #include <netinet/ip.h> 91 #include <netinet/tcp_var.h> 92 93 #ifdef SIFTR_IPV6 94 #include <netinet/ip6.h> 95 #include <netinet6/in6_pcb.h> 96 #endif /* SIFTR_IPV6 */ 97 98 #include <machine/in_cksum.h> 99 100 /* 101 * Three digit version number refers to X.Y.Z where: 102 * X is the major version number 103 * Y is bumped to mark backwards incompatible changes 104 * Z is bumped to mark backwards compatible changes 105 */ 106 #define V_MAJOR 1 107 #define V_BACKBREAK 2 108 #define V_BACKCOMPAT 4 109 #define MODVERSION __CONCAT(V_MAJOR, __CONCAT(V_BACKBREAK, V_BACKCOMPAT)) 110 #define MODVERSION_STR __XSTRING(V_MAJOR) "." __XSTRING(V_BACKBREAK) "." \ 111 __XSTRING(V_BACKCOMPAT) 112 113 #define HOOK 0 114 #define UNHOOK 1 115 #define SIFTR_EXPECTED_MAX_TCP_FLOWS 65536 116 #define SYS_NAME "FreeBSD" 117 #define PACKET_TAG_SIFTR 100 118 #define PACKET_COOKIE_SIFTR 21749576 119 #define SIFTR_LOG_FILE_MODE 0644 120 #define SIFTR_DISABLE 0 121 #define SIFTR_ENABLE 1 122 123 /* 124 * Hard upper limit on the length of log messages. Bump this up if you add new 125 * data fields such that the line length could exceed the below value. 126 */ 127 #define MAX_LOG_MSG_LEN 200 128 /* XXX: Make this a sysctl tunable. */ 129 #define SIFTR_ALQ_BUFLEN (1000*MAX_LOG_MSG_LEN) 130 131 /* 132 * 1 byte for IP version 133 * IPv4: src/dst IP (4+4) + src/dst port (2+2) = 12 bytes 134 * IPv6: src/dst IP (16+16) + src/dst port (2+2) = 36 bytes 135 */ 136 #ifdef SIFTR_IPV6 137 #define FLOW_KEY_LEN 37 138 #else 139 #define FLOW_KEY_LEN 13 140 #endif 141 142 #ifdef SIFTR_IPV6 143 #define SIFTR_IPMODE 6 144 #else 145 #define SIFTR_IPMODE 4 146 #endif 147 148 /* useful macros */ 149 #define CAST_PTR_INT(X) (*((int*)(X))) 150 151 #define UPPER_SHORT(X) (((X) & 0xFFFF0000) >> 16) 152 #define LOWER_SHORT(X) ((X) & 0x0000FFFF) 153 154 #define FIRST_OCTET(X) (((X) & 0xFF000000) >> 24) 155 #define SECOND_OCTET(X) (((X) & 0x00FF0000) >> 16) 156 #define THIRD_OCTET(X) (((X) & 0x0000FF00) >> 8) 157 #define FOURTH_OCTET(X) ((X) & 0x000000FF) 158 159 static MALLOC_DEFINE(M_SIFTR, "siftr", "dynamic memory used by SIFTR"); 160 static MALLOC_DEFINE(M_SIFTR_PKTNODE, "siftr_pktnode", 161 "SIFTR pkt_node struct"); 162 static MALLOC_DEFINE(M_SIFTR_HASHNODE, "siftr_hashnode", 163 "SIFTR flow_hash_node struct"); 164 165 /* Used as links in the pkt manager queue. */ 166 struct pkt_node { 167 /* Timestamp of pkt as noted in the pfil hook. */ 168 struct timeval tval; 169 /* Direction pkt is travelling; either PFIL_IN or PFIL_OUT. */ 170 uint8_t direction; 171 /* IP version pkt_node relates to; either INP_IPV4 or INP_IPV6. */ 172 uint8_t ipver; 173 /* Hash of the pkt which triggered the log message. */ 174 uint32_t hash; 175 /* Local/foreign IP address. */ 176 #ifdef SIFTR_IPV6 177 uint32_t ip_laddr[4]; 178 uint32_t ip_faddr[4]; 179 #else 180 uint8_t ip_laddr[4]; 181 uint8_t ip_faddr[4]; 182 #endif 183 /* Local TCP port. */ 184 uint16_t tcp_localport; 185 /* Foreign TCP port. */ 186 uint16_t tcp_foreignport; 187 /* Congestion Window (bytes). */ 188 u_long snd_cwnd; 189 /* Sending Window (bytes). */ 190 u_long snd_wnd; 191 /* Receive Window (bytes). */ 192 u_long rcv_wnd; 193 /* Unused (was: Bandwidth Controlled Window (bytes)). */ 194 u_long snd_bwnd; 195 /* Slow Start Threshold (bytes). */ 196 u_long snd_ssthresh; 197 /* Current state of the TCP FSM. */ 198 int conn_state; 199 /* Max Segment Size (bytes). */ 200 u_int max_seg_size; 201 /* 202 * Smoothed RTT stored as found in the TCP control block 203 * in units of (TCP_RTT_SCALE*hz). 204 */ 205 int smoothed_rtt; 206 /* Is SACK enabled? */ 207 u_char sack_enabled; 208 /* Window scaling for snd window. */ 209 u_char snd_scale; 210 /* Window scaling for recv window. */ 211 u_char rcv_scale; 212 /* TCP control block flags. */ 213 u_int flags; 214 /* Retransmit timeout length. */ 215 int rxt_length; 216 /* Size of the TCP send buffer in bytes. */ 217 u_int snd_buf_hiwater; 218 /* Current num bytes in the send socket buffer. */ 219 u_int snd_buf_cc; 220 /* Size of the TCP receive buffer in bytes. */ 221 u_int rcv_buf_hiwater; 222 /* Current num bytes in the receive socket buffer. */ 223 u_int rcv_buf_cc; 224 /* Number of bytes inflight that we are waiting on ACKs for. */ 225 u_int sent_inflight_bytes; 226 /* Number of segments currently in the reassembly queue. */ 227 int t_segqlen; 228 /* Link to next pkt_node in the list. */ 229 STAILQ_ENTRY(pkt_node) nodes; 230 }; 231 232 struct flow_hash_node 233 { 234 uint16_t counter; 235 uint8_t key[FLOW_KEY_LEN]; 236 LIST_ENTRY(flow_hash_node) nodes; 237 }; 238 239 struct siftr_stats 240 { 241 /* # TCP pkts seen by the SIFTR PFIL hooks, including any skipped. */ 242 uint64_t n_in; 243 uint64_t n_out; 244 /* # pkts skipped due to failed malloc calls. */ 245 uint32_t nskip_in_malloc; 246 uint32_t nskip_out_malloc; 247 /* # pkts skipped due to failed mtx acquisition. */ 248 uint32_t nskip_in_mtx; 249 uint32_t nskip_out_mtx; 250 /* # pkts skipped due to failed inpcb lookups. */ 251 uint32_t nskip_in_inpcb; 252 uint32_t nskip_out_inpcb; 253 /* # pkts skipped due to failed tcpcb lookups. */ 254 uint32_t nskip_in_tcpcb; 255 uint32_t nskip_out_tcpcb; 256 /* # pkts skipped due to stack reinjection. */ 257 uint32_t nskip_in_dejavu; 258 uint32_t nskip_out_dejavu; 259 }; 260 261 static DPCPU_DEFINE(struct siftr_stats, ss); 262 263 static volatile unsigned int siftr_exit_pkt_manager_thread = 0; 264 static unsigned int siftr_enabled = 0; 265 static unsigned int siftr_pkts_per_log = 1; 266 static unsigned int siftr_generate_hashes = 0; 267 /* static unsigned int siftr_binary_log = 0; */ 268 static char siftr_logfile[PATH_MAX] = "/var/log/siftr.log"; 269 static u_long siftr_hashmask; 270 STAILQ_HEAD(pkthead, pkt_node) pkt_queue = STAILQ_HEAD_INITIALIZER(pkt_queue); 271 LIST_HEAD(listhead, flow_hash_node) *counter_hash; 272 static int wait_for_pkt; 273 static struct alq *siftr_alq = NULL; 274 static struct mtx siftr_pkt_queue_mtx; 275 static struct mtx siftr_pkt_mgr_mtx; 276 static struct thread *siftr_pkt_manager_thr = NULL; 277 /* 278 * pfil.h defines PFIL_IN as 1 and PFIL_OUT as 2, 279 * which we use as an index into this array. 280 */ 281 static char direction[3] = {'\0', 'i','o'}; 282 283 /* Required function prototypes. */ 284 static int siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS); 285 static int siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS); 286 287 288 /* Declare the net.inet.siftr sysctl tree and populate it. */ 289 290 SYSCTL_DECL(_net_inet_siftr); 291 292 SYSCTL_NODE(_net_inet, OID_AUTO, siftr, CTLFLAG_RW, NULL, 293 "siftr related settings"); 294 295 SYSCTL_PROC(_net_inet_siftr, OID_AUTO, enabled, CTLTYPE_UINT|CTLFLAG_RW, 296 &siftr_enabled, 0, &siftr_sysctl_enabled_handler, "IU", 297 "switch siftr module operations on/off"); 298 299 SYSCTL_PROC(_net_inet_siftr, OID_AUTO, logfile, CTLTYPE_STRING|CTLFLAG_RW, 300 &siftr_logfile, sizeof(siftr_logfile), &siftr_sysctl_logfile_name_handler, 301 "A", "file to save siftr log messages to"); 302 303 SYSCTL_UINT(_net_inet_siftr, OID_AUTO, ppl, CTLFLAG_RW, 304 &siftr_pkts_per_log, 1, 305 "number of packets between generating a log message"); 306 307 SYSCTL_UINT(_net_inet_siftr, OID_AUTO, genhashes, CTLFLAG_RW, 308 &siftr_generate_hashes, 0, 309 "enable packet hash generation"); 310 311 /* XXX: TODO 312 SYSCTL_UINT(_net_inet_siftr, OID_AUTO, binary, CTLFLAG_RW, 313 &siftr_binary_log, 0, 314 "write log files in binary instead of ascii"); 315 */ 316 317 318 /* Begin functions. */ 319 320 static void 321 siftr_process_pkt(struct pkt_node * pkt_node) 322 { 323 struct flow_hash_node *hash_node; 324 struct listhead *counter_list; 325 struct siftr_stats *ss; 326 struct ale *log_buf; 327 uint8_t key[FLOW_KEY_LEN]; 328 uint8_t found_match, key_offset; 329 330 hash_node = NULL; 331 ss = DPCPU_PTR(ss); 332 found_match = 0; 333 key_offset = 1; 334 335 /* 336 * Create the key that will be used to create a hash index 337 * into our hash table. Our key consists of: 338 * ipversion, localip, localport, foreignip, foreignport 339 */ 340 key[0] = pkt_node->ipver; 341 memcpy(key + key_offset, &pkt_node->ip_laddr, 342 sizeof(pkt_node->ip_laddr)); 343 key_offset += sizeof(pkt_node->ip_laddr); 344 memcpy(key + key_offset, &pkt_node->tcp_localport, 345 sizeof(pkt_node->tcp_localport)); 346 key_offset += sizeof(pkt_node->tcp_localport); 347 memcpy(key + key_offset, &pkt_node->ip_faddr, 348 sizeof(pkt_node->ip_faddr)); 349 key_offset += sizeof(pkt_node->ip_faddr); 350 memcpy(key + key_offset, &pkt_node->tcp_foreignport, 351 sizeof(pkt_node->tcp_foreignport)); 352 353 counter_list = counter_hash + 354 (hash32_buf(key, sizeof(key), 0) & siftr_hashmask); 355 356 /* 357 * If the list is not empty i.e. the hash index has 358 * been used by another flow previously. 359 */ 360 if (LIST_FIRST(counter_list) != NULL) { 361 /* 362 * Loop through the hash nodes in the list. 363 * There should normally only be 1 hash node in the list, 364 * except if there have been collisions at the hash index 365 * computed by hash32_buf(). 366 */ 367 LIST_FOREACH(hash_node, counter_list, nodes) { 368 /* 369 * Check if the key for the pkt we are currently 370 * processing is the same as the key stored in the 371 * hash node we are currently processing. 372 * If they are the same, then we've found the 373 * hash node that stores the counter for the flow 374 * the pkt belongs to. 375 */ 376 if (memcmp(hash_node->key, key, sizeof(key)) == 0) { 377 found_match = 1; 378 break; 379 } 380 } 381 } 382 383 /* If this flow hash hasn't been seen before or we have a collision. */ 384 if (hash_node == NULL || !found_match) { 385 /* Create a new hash node to store the flow's counter. */ 386 hash_node = malloc(sizeof(struct flow_hash_node), 387 M_SIFTR_HASHNODE, M_WAITOK); 388 389 if (hash_node != NULL) { 390 /* Initialise our new hash node list entry. */ 391 hash_node->counter = 0; 392 memcpy(hash_node->key, key, sizeof(key)); 393 LIST_INSERT_HEAD(counter_list, hash_node, nodes); 394 } else { 395 /* Malloc failed. */ 396 if (pkt_node->direction == PFIL_IN) 397 ss->nskip_in_malloc++; 398 else 399 ss->nskip_out_malloc++; 400 401 return; 402 } 403 } else if (siftr_pkts_per_log > 1) { 404 /* 405 * Taking the remainder of the counter divided 406 * by the current value of siftr_pkts_per_log 407 * and storing that in counter provides a neat 408 * way to modulate the frequency of log 409 * messages being written to the log file. 410 */ 411 hash_node->counter = (hash_node->counter + 1) % 412 siftr_pkts_per_log; 413 414 /* 415 * If we have not seen enough packets since the last time 416 * we wrote a log message for this connection, return. 417 */ 418 if (hash_node->counter > 0) 419 return; 420 } 421 422 log_buf = alq_getn(siftr_alq, MAX_LOG_MSG_LEN, ALQ_WAITOK); 423 424 if (log_buf == NULL) 425 return; /* Should only happen if the ALQ is shutting down. */ 426 427 #ifdef SIFTR_IPV6 428 pkt_node->ip_laddr[3] = ntohl(pkt_node->ip_laddr[3]); 429 pkt_node->ip_faddr[3] = ntohl(pkt_node->ip_faddr[3]); 430 431 if (pkt_node->ipver == INP_IPV6) { /* IPv6 packet */ 432 pkt_node->ip_laddr[0] = ntohl(pkt_node->ip_laddr[0]); 433 pkt_node->ip_laddr[1] = ntohl(pkt_node->ip_laddr[1]); 434 pkt_node->ip_laddr[2] = ntohl(pkt_node->ip_laddr[2]); 435 pkt_node->ip_faddr[0] = ntohl(pkt_node->ip_faddr[0]); 436 pkt_node->ip_faddr[1] = ntohl(pkt_node->ip_faddr[1]); 437 pkt_node->ip_faddr[2] = ntohl(pkt_node->ip_faddr[2]); 438 439 /* Construct an IPv6 log message. */ 440 log_buf->ae_bytesused = snprintf(log_buf->ae_data, 441 MAX_LOG_MSG_LEN, 442 "%c,0x%08x,%zd.%06ld,%x:%x:%x:%x:%x:%x:%x:%x,%u,%x:%x:%x:" 443 "%x:%x:%x:%x:%x,%u,%ld,%ld,%ld,%ld,%ld,%u,%u,%u,%u,%u,%u," 444 "%u,%d,%u,%u,%u,%u,%u,%u\n", 445 direction[pkt_node->direction], 446 pkt_node->hash, 447 pkt_node->tval.tv_sec, 448 pkt_node->tval.tv_usec, 449 UPPER_SHORT(pkt_node->ip_laddr[0]), 450 LOWER_SHORT(pkt_node->ip_laddr[0]), 451 UPPER_SHORT(pkt_node->ip_laddr[1]), 452 LOWER_SHORT(pkt_node->ip_laddr[1]), 453 UPPER_SHORT(pkt_node->ip_laddr[2]), 454 LOWER_SHORT(pkt_node->ip_laddr[2]), 455 UPPER_SHORT(pkt_node->ip_laddr[3]), 456 LOWER_SHORT(pkt_node->ip_laddr[3]), 457 ntohs(pkt_node->tcp_localport), 458 UPPER_SHORT(pkt_node->ip_faddr[0]), 459 LOWER_SHORT(pkt_node->ip_faddr[0]), 460 UPPER_SHORT(pkt_node->ip_faddr[1]), 461 LOWER_SHORT(pkt_node->ip_faddr[1]), 462 UPPER_SHORT(pkt_node->ip_faddr[2]), 463 LOWER_SHORT(pkt_node->ip_faddr[2]), 464 UPPER_SHORT(pkt_node->ip_faddr[3]), 465 LOWER_SHORT(pkt_node->ip_faddr[3]), 466 ntohs(pkt_node->tcp_foreignport), 467 pkt_node->snd_ssthresh, 468 pkt_node->snd_cwnd, 469 pkt_node->snd_bwnd, 470 pkt_node->snd_wnd, 471 pkt_node->rcv_wnd, 472 pkt_node->snd_scale, 473 pkt_node->rcv_scale, 474 pkt_node->conn_state, 475 pkt_node->max_seg_size, 476 pkt_node->smoothed_rtt, 477 pkt_node->sack_enabled, 478 pkt_node->flags, 479 pkt_node->rxt_length, 480 pkt_node->snd_buf_hiwater, 481 pkt_node->snd_buf_cc, 482 pkt_node->rcv_buf_hiwater, 483 pkt_node->rcv_buf_cc, 484 pkt_node->sent_inflight_bytes, 485 pkt_node->t_segqlen); 486 } else { /* IPv4 packet */ 487 pkt_node->ip_laddr[0] = FIRST_OCTET(pkt_node->ip_laddr[3]); 488 pkt_node->ip_laddr[1] = SECOND_OCTET(pkt_node->ip_laddr[3]); 489 pkt_node->ip_laddr[2] = THIRD_OCTET(pkt_node->ip_laddr[3]); 490 pkt_node->ip_laddr[3] = FOURTH_OCTET(pkt_node->ip_laddr[3]); 491 pkt_node->ip_faddr[0] = FIRST_OCTET(pkt_node->ip_faddr[3]); 492 pkt_node->ip_faddr[1] = SECOND_OCTET(pkt_node->ip_faddr[3]); 493 pkt_node->ip_faddr[2] = THIRD_OCTET(pkt_node->ip_faddr[3]); 494 pkt_node->ip_faddr[3] = FOURTH_OCTET(pkt_node->ip_faddr[3]); 495 #endif /* SIFTR_IPV6 */ 496 497 /* Construct an IPv4 log message. */ 498 log_buf->ae_bytesused = snprintf(log_buf->ae_data, 499 MAX_LOG_MSG_LEN, 500 "%c,0x%08x,%jd.%06ld,%u.%u.%u.%u,%u,%u.%u.%u.%u,%u,%ld,%ld," 501 "%ld,%ld,%ld,%u,%u,%u,%u,%u,%u,%u,%d,%u,%u,%u,%u,%u,%u\n", 502 direction[pkt_node->direction], 503 pkt_node->hash, 504 (intmax_t)pkt_node->tval.tv_sec, 505 pkt_node->tval.tv_usec, 506 pkt_node->ip_laddr[0], 507 pkt_node->ip_laddr[1], 508 pkt_node->ip_laddr[2], 509 pkt_node->ip_laddr[3], 510 ntohs(pkt_node->tcp_localport), 511 pkt_node->ip_faddr[0], 512 pkt_node->ip_faddr[1], 513 pkt_node->ip_faddr[2], 514 pkt_node->ip_faddr[3], 515 ntohs(pkt_node->tcp_foreignport), 516 pkt_node->snd_ssthresh, 517 pkt_node->snd_cwnd, 518 pkt_node->snd_bwnd, 519 pkt_node->snd_wnd, 520 pkt_node->rcv_wnd, 521 pkt_node->snd_scale, 522 pkt_node->rcv_scale, 523 pkt_node->conn_state, 524 pkt_node->max_seg_size, 525 pkt_node->smoothed_rtt, 526 pkt_node->sack_enabled, 527 pkt_node->flags, 528 pkt_node->rxt_length, 529 pkt_node->snd_buf_hiwater, 530 pkt_node->snd_buf_cc, 531 pkt_node->rcv_buf_hiwater, 532 pkt_node->rcv_buf_cc, 533 pkt_node->sent_inflight_bytes, 534 pkt_node->t_segqlen); 535 #ifdef SIFTR_IPV6 536 } 537 #endif 538 539 alq_post_flags(siftr_alq, log_buf, 0); 540 } 541 542 543 static void 544 siftr_pkt_manager_thread(void *arg) 545 { 546 STAILQ_HEAD(pkthead, pkt_node) tmp_pkt_queue = 547 STAILQ_HEAD_INITIALIZER(tmp_pkt_queue); 548 struct pkt_node *pkt_node, *pkt_node_temp; 549 uint8_t draining; 550 551 draining = 2; 552 553 mtx_lock(&siftr_pkt_mgr_mtx); 554 555 /* draining == 0 when queue has been flushed and it's safe to exit. */ 556 while (draining) { 557 /* 558 * Sleep until we are signalled to wake because thread has 559 * been told to exit or until 1 tick has passed. 560 */ 561 mtx_sleep(&wait_for_pkt, &siftr_pkt_mgr_mtx, PWAIT, "pktwait", 562 1); 563 564 /* Gain exclusive access to the pkt_node queue. */ 565 mtx_lock(&siftr_pkt_queue_mtx); 566 567 /* 568 * Move pkt_queue to tmp_pkt_queue, which leaves 569 * pkt_queue empty and ready to receive more pkt_nodes. 570 */ 571 STAILQ_CONCAT(&tmp_pkt_queue, &pkt_queue); 572 573 /* 574 * We've finished making changes to the list. Unlock it 575 * so the pfil hooks can continue queuing pkt_nodes. 576 */ 577 mtx_unlock(&siftr_pkt_queue_mtx); 578 579 /* 580 * We can't hold a mutex whilst calling siftr_process_pkt 581 * because ALQ might sleep waiting for buffer space. 582 */ 583 mtx_unlock(&siftr_pkt_mgr_mtx); 584 585 /* Flush all pkt_nodes to the log file. */ 586 STAILQ_FOREACH_SAFE(pkt_node, &tmp_pkt_queue, nodes, 587 pkt_node_temp) { 588 siftr_process_pkt(pkt_node); 589 STAILQ_REMOVE_HEAD(&tmp_pkt_queue, nodes); 590 free(pkt_node, M_SIFTR_PKTNODE); 591 } 592 593 KASSERT(STAILQ_EMPTY(&tmp_pkt_queue), 594 ("SIFTR tmp_pkt_queue not empty after flush")); 595 596 mtx_lock(&siftr_pkt_mgr_mtx); 597 598 /* 599 * If siftr_exit_pkt_manager_thread gets set during the window 600 * where we are draining the tmp_pkt_queue above, there might 601 * still be pkts in pkt_queue that need to be drained. 602 * Allow one further iteration to occur after 603 * siftr_exit_pkt_manager_thread has been set to ensure 604 * pkt_queue is completely empty before we kill the thread. 605 * 606 * siftr_exit_pkt_manager_thread is set only after the pfil 607 * hooks have been removed, so only 1 extra iteration 608 * is needed to drain the queue. 609 */ 610 if (siftr_exit_pkt_manager_thread) 611 draining--; 612 } 613 614 mtx_unlock(&siftr_pkt_mgr_mtx); 615 616 /* Calls wakeup on this thread's struct thread ptr. */ 617 kthread_exit(); 618 } 619 620 621 static uint32_t 622 hash_pkt(struct mbuf *m, uint32_t offset) 623 { 624 uint32_t hash; 625 626 hash = 0; 627 628 while (m != NULL && offset > m->m_len) { 629 /* 630 * The IP packet payload does not start in this mbuf, so 631 * need to figure out which mbuf it starts in and what offset 632 * into the mbuf's data region the payload starts at. 633 */ 634 offset -= m->m_len; 635 m = m->m_next; 636 } 637 638 while (m != NULL) { 639 /* Ensure there is data in the mbuf */ 640 if ((m->m_len - offset) > 0) 641 hash = hash32_buf(m->m_data + offset, 642 m->m_len - offset, hash); 643 644 m = m->m_next; 645 offset = 0; 646 } 647 648 return (hash); 649 } 650 651 652 /* 653 * Check if a given mbuf has the SIFTR mbuf tag. If it does, log the fact that 654 * it's a reinjected packet and return. If it doesn't, tag the mbuf and return. 655 * Return value >0 means the caller should skip processing this mbuf. 656 */ 657 static inline int 658 siftr_chkreinject(struct mbuf *m, int dir, struct siftr_stats *ss) 659 { 660 if (m_tag_locate(m, PACKET_COOKIE_SIFTR, PACKET_TAG_SIFTR, NULL) 661 != NULL) { 662 if (dir == PFIL_IN) 663 ss->nskip_in_dejavu++; 664 else 665 ss->nskip_out_dejavu++; 666 667 return (1); 668 } else { 669 struct m_tag *tag = m_tag_alloc(PACKET_COOKIE_SIFTR, 670 PACKET_TAG_SIFTR, 0, M_NOWAIT); 671 if (tag == NULL) { 672 if (dir == PFIL_IN) 673 ss->nskip_in_malloc++; 674 else 675 ss->nskip_out_malloc++; 676 677 return (1); 678 } 679 680 m_tag_prepend(m, tag); 681 } 682 683 return (0); 684 } 685 686 687 /* 688 * Look up an inpcb for a packet. Return the inpcb pointer if found, or NULL 689 * otherwise. 690 */ 691 static inline struct inpcb * 692 siftr_findinpcb(int ipver, struct ip *ip, struct mbuf *m, uint16_t sport, 693 uint16_t dport, int dir, struct siftr_stats *ss) 694 { 695 struct inpcb *inp; 696 697 /* We need the tcbinfo lock. */ 698 INP_INFO_UNLOCK_ASSERT(&V_tcbinfo); 699 INP_INFO_RLOCK(&V_tcbinfo); 700 701 if (dir == PFIL_IN) 702 inp = (ipver == INP_IPV4 ? 703 in_pcblookup_hash(&V_tcbinfo, ip->ip_src, sport, ip->ip_dst, 704 dport, 0, m->m_pkthdr.rcvif) 705 : 706 #ifdef SIFTR_IPV6 707 in6_pcblookup_hash(&V_tcbinfo, 708 &((struct ip6_hdr *)ip)->ip6_src, sport, 709 &((struct ip6_hdr *)ip)->ip6_dst, dport, 0, 710 m->m_pkthdr.rcvif) 711 #else 712 NULL 713 #endif 714 ); 715 716 else 717 inp = (ipver == INP_IPV4 ? 718 in_pcblookup_hash(&V_tcbinfo, ip->ip_dst, dport, ip->ip_src, 719 sport, 0, m->m_pkthdr.rcvif) 720 : 721 #ifdef SIFTR_IPV6 722 in6_pcblookup_hash(&V_tcbinfo, 723 &((struct ip6_hdr *)ip)->ip6_dst, dport, 724 &((struct ip6_hdr *)ip)->ip6_src, sport, 0, 725 m->m_pkthdr.rcvif) 726 #else 727 NULL 728 #endif 729 ); 730 731 /* If we can't find the inpcb, bail. */ 732 if (inp == NULL) { 733 if (dir == PFIL_IN) 734 ss->nskip_in_inpcb++; 735 else 736 ss->nskip_out_inpcb++; 737 } else { 738 /* Acquire the inpcb lock. */ 739 INP_UNLOCK_ASSERT(inp); 740 INP_RLOCK(inp); 741 } 742 INP_INFO_RUNLOCK(&V_tcbinfo); 743 744 return (inp); 745 } 746 747 748 static inline void 749 siftr_siftdata(struct pkt_node *pn, struct inpcb *inp, struct tcpcb *tp, 750 int ipver, int dir, int inp_locally_locked) 751 { 752 #ifdef SIFTR_IPV6 753 if (ipver == INP_IPV4) { 754 pn->ip_laddr[3] = inp->inp_laddr.s_addr; 755 pn->ip_faddr[3] = inp->inp_faddr.s_addr; 756 #else 757 *((uint32_t *)pn->ip_laddr) = inp->inp_laddr.s_addr; 758 *((uint32_t *)pn->ip_faddr) = inp->inp_faddr.s_addr; 759 #endif 760 #ifdef SIFTR_IPV6 761 } else { 762 pn->ip_laddr[0] = inp->in6p_laddr.s6_addr32[0]; 763 pn->ip_laddr[1] = inp->in6p_laddr.s6_addr32[1]; 764 pn->ip_laddr[2] = inp->in6p_laddr.s6_addr32[2]; 765 pn->ip_laddr[3] = inp->in6p_laddr.s6_addr32[3]; 766 pn->ip_faddr[0] = inp->in6p_faddr.s6_addr32[0]; 767 pn->ip_faddr[1] = inp->in6p_faddr.s6_addr32[1]; 768 pn->ip_faddr[2] = inp->in6p_faddr.s6_addr32[2]; 769 pn->ip_faddr[3] = inp->in6p_faddr.s6_addr32[3]; 770 } 771 #endif 772 pn->tcp_localport = inp->inp_lport; 773 pn->tcp_foreignport = inp->inp_fport; 774 pn->snd_cwnd = tp->snd_cwnd; 775 pn->snd_wnd = tp->snd_wnd; 776 pn->rcv_wnd = tp->rcv_wnd; 777 pn->snd_bwnd = 0; /* Unused, kept for compat. */ 778 pn->snd_ssthresh = tp->snd_ssthresh; 779 pn->snd_scale = tp->snd_scale; 780 pn->rcv_scale = tp->rcv_scale; 781 pn->conn_state = tp->t_state; 782 pn->max_seg_size = tp->t_maxseg; 783 pn->smoothed_rtt = tp->t_srtt; 784 pn->sack_enabled = (tp->t_flags & TF_SACK_PERMIT) != 0; 785 pn->flags = tp->t_flags; 786 pn->rxt_length = tp->t_rxtcur; 787 pn->snd_buf_hiwater = inp->inp_socket->so_snd.sb_hiwat; 788 pn->snd_buf_cc = inp->inp_socket->so_snd.sb_cc; 789 pn->rcv_buf_hiwater = inp->inp_socket->so_rcv.sb_hiwat; 790 pn->rcv_buf_cc = inp->inp_socket->so_rcv.sb_cc; 791 pn->sent_inflight_bytes = tp->snd_max - tp->snd_una; 792 pn->t_segqlen = tp->t_segqlen; 793 794 /* We've finished accessing the tcb so release the lock. */ 795 if (inp_locally_locked) 796 INP_RUNLOCK(inp); 797 798 pn->ipver = ipver; 799 pn->direction = dir; 800 801 /* 802 * Significantly more accurate than using getmicrotime(), but slower! 803 * Gives true microsecond resolution at the expense of a hit to 804 * maximum pps throughput processing when SIFTR is loaded and enabled. 805 */ 806 microtime(&pn->tval); 807 } 808 809 810 /* 811 * pfil hook that is called for each IPv4 packet making its way through the 812 * stack in either direction. 813 * The pfil subsystem holds a non-sleepable mutex somewhere when 814 * calling our hook function, so we can't sleep at all. 815 * It's very important to use the M_NOWAIT flag with all function calls 816 * that support it so that they won't sleep, otherwise you get a panic. 817 */ 818 static int 819 siftr_chkpkt(void *arg, struct mbuf **m, struct ifnet *ifp, int dir, 820 struct inpcb *inp) 821 { 822 struct pkt_node *pn; 823 struct ip *ip; 824 struct tcphdr *th; 825 struct tcpcb *tp; 826 struct siftr_stats *ss; 827 unsigned int ip_hl; 828 int inp_locally_locked; 829 830 inp_locally_locked = 0; 831 ss = DPCPU_PTR(ss); 832 833 /* 834 * m_pullup is not required here because ip_{input|output} 835 * already do the heavy lifting for us. 836 */ 837 838 ip = mtod(*m, struct ip *); 839 840 /* Only continue processing if the packet is TCP. */ 841 if (ip->ip_p != IPPROTO_TCP) 842 goto ret; 843 844 /* 845 * If a kernel subsystem reinjects packets into the stack, our pfil 846 * hook will be called multiple times for the same packet. 847 * Make sure we only process unique packets. 848 */ 849 if (siftr_chkreinject(*m, dir, ss)) 850 goto ret; 851 852 if (dir == PFIL_IN) 853 ss->n_in++; 854 else 855 ss->n_out++; 856 857 /* 858 * Create a tcphdr struct starting at the correct offset 859 * in the IP packet. ip->ip_hl gives the ip header length 860 * in 4-byte words, so multiply it to get the size in bytes. 861 */ 862 ip_hl = (ip->ip_hl << 2); 863 th = (struct tcphdr *)((caddr_t)ip + ip_hl); 864 865 /* 866 * If the pfil hooks don't provide a pointer to the 867 * inpcb, we need to find it ourselves and lock it. 868 */ 869 if (!inp) { 870 /* Find the corresponding inpcb for this pkt. */ 871 inp = siftr_findinpcb(INP_IPV4, ip, *m, th->th_sport, 872 th->th_dport, dir, ss); 873 874 if (inp == NULL) 875 goto ret; 876 else 877 inp_locally_locked = 1; 878 } 879 880 INP_LOCK_ASSERT(inp); 881 882 /* Find the TCP control block that corresponds with this packet */ 883 tp = intotcpcb(inp); 884 885 /* 886 * If we can't find the TCP control block (happens occasionaly for a 887 * packet sent during the shutdown phase of a TCP connection), 888 * or we're in the timewait state, bail 889 */ 890 if (tp == NULL || inp->inp_flags & INP_TIMEWAIT) { 891 if (dir == PFIL_IN) 892 ss->nskip_in_tcpcb++; 893 else 894 ss->nskip_out_tcpcb++; 895 896 goto inp_unlock; 897 } 898 899 pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO); 900 901 if (pn == NULL) { 902 if (dir == PFIL_IN) 903 ss->nskip_in_malloc++; 904 else 905 ss->nskip_out_malloc++; 906 907 goto inp_unlock; 908 } 909 910 siftr_siftdata(pn, inp, tp, INP_IPV4, dir, inp_locally_locked); 911 912 if (siftr_generate_hashes) { 913 if ((*m)->m_pkthdr.csum_flags & CSUM_TCP) { 914 /* 915 * For outbound packets, the TCP checksum isn't 916 * calculated yet. This is a problem for our packet 917 * hashing as the receiver will calc a different hash 918 * to ours if we don't include the correct TCP checksum 919 * in the bytes being hashed. To work around this 920 * problem, we manually calc the TCP checksum here in 921 * software. We unset the CSUM_TCP flag so the lower 922 * layers don't recalc it. 923 */ 924 (*m)->m_pkthdr.csum_flags &= ~CSUM_TCP; 925 926 /* 927 * Calculate the TCP checksum in software and assign 928 * to correct TCP header field, which will follow the 929 * packet mbuf down the stack. The trick here is that 930 * tcp_output() sets th->th_sum to the checksum of the 931 * pseudo header for us already. Because of the nature 932 * of the checksumming algorithm, we can sum over the 933 * entire IP payload (i.e. TCP header and data), which 934 * will include the already calculated pseduo header 935 * checksum, thus giving us the complete TCP checksum. 936 * 937 * To put it in simple terms, if checksum(1,2,3,4)=10, 938 * then checksum(1,2,3,4,5) == checksum(10,5). 939 * This property is what allows us to "cheat" and 940 * checksum only the IP payload which has the TCP 941 * th_sum field populated with the pseudo header's 942 * checksum, and not need to futz around checksumming 943 * pseudo header bytes and TCP header/data in one hit. 944 * Refer to RFC 1071 for more info. 945 * 946 * NB: in_cksum_skip(struct mbuf *m, int len, int skip) 947 * in_cksum_skip 2nd argument is NOT the number of 948 * bytes to read from the mbuf at "skip" bytes offset 949 * from the start of the mbuf (very counter intuitive!). 950 * The number of bytes to read is calculated internally 951 * by the function as len-skip i.e. to sum over the IP 952 * payload (TCP header + data) bytes, it is INCORRECT 953 * to call the function like this: 954 * in_cksum_skip(at, ip->ip_len - offset, offset) 955 * Rather, it should be called like this: 956 * in_cksum_skip(at, ip->ip_len, offset) 957 * which means read "ip->ip_len - offset" bytes from 958 * the mbuf cluster "at" at offset "offset" bytes from 959 * the beginning of the "at" mbuf's data pointer. 960 */ 961 th->th_sum = in_cksum_skip(*m, ip->ip_len, ip_hl); 962 } 963 964 /* 965 * XXX: Having to calculate the checksum in software and then 966 * hash over all bytes is really inefficient. Would be nice to 967 * find a way to create the hash and checksum in the same pass 968 * over the bytes. 969 */ 970 pn->hash = hash_pkt(*m, ip_hl); 971 } 972 973 mtx_lock(&siftr_pkt_queue_mtx); 974 STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes); 975 mtx_unlock(&siftr_pkt_queue_mtx); 976 goto ret; 977 978 inp_unlock: 979 if (inp_locally_locked) 980 INP_RUNLOCK(inp); 981 982 ret: 983 /* Returning 0 ensures pfil will not discard the pkt */ 984 return (0); 985 } 986 987 988 #ifdef SIFTR_IPV6 989 static int 990 siftr_chkpkt6(void *arg, struct mbuf **m, struct ifnet *ifp, int dir, 991 struct inpcb *inp) 992 { 993 struct pkt_node *pn; 994 struct ip6_hdr *ip6; 995 struct tcphdr *th; 996 struct tcpcb *tp; 997 struct siftr_stats *ss; 998 unsigned int ip6_hl; 999 int inp_locally_locked; 1000 1001 inp_locally_locked = 0; 1002 ss = DPCPU_PTR(ss); 1003 1004 /* 1005 * m_pullup is not required here because ip6_{input|output} 1006 * already do the heavy lifting for us. 1007 */ 1008 1009 ip6 = mtod(*m, struct ip6_hdr *); 1010 1011 /* 1012 * Only continue processing if the packet is TCP 1013 * XXX: We should follow the next header fields 1014 * as shown on Pg 6 RFC 2460, but right now we'll 1015 * only check pkts that have no extension headers. 1016 */ 1017 if (ip6->ip6_nxt != IPPROTO_TCP) 1018 goto ret6; 1019 1020 /* 1021 * If a kernel subsystem reinjects packets into the stack, our pfil 1022 * hook will be called multiple times for the same packet. 1023 * Make sure we only process unique packets. 1024 */ 1025 if (siftr_chkreinject(*m, dir, ss)) 1026 goto ret6; 1027 1028 if (dir == PFIL_IN) 1029 ss->n_in++; 1030 else 1031 ss->n_out++; 1032 1033 ip6_hl = sizeof(struct ip6_hdr); 1034 1035 /* 1036 * Create a tcphdr struct starting at the correct offset 1037 * in the ipv6 packet. ip->ip_hl gives the ip header length 1038 * in 4-byte words, so multiply it to get the size in bytes. 1039 */ 1040 th = (struct tcphdr *)((caddr_t)ip6 + ip6_hl); 1041 1042 /* 1043 * For inbound packets, the pfil hooks don't provide a pointer to the 1044 * inpcb, so we need to find it ourselves and lock it. 1045 */ 1046 if (!inp) { 1047 /* Find the corresponding inpcb for this pkt. */ 1048 inp = siftr_findinpcb(INP_IPV6, (struct ip *)ip6, *m, 1049 th->th_sport, th->th_dport, dir, ss); 1050 1051 if (inp == NULL) 1052 goto ret6; 1053 else 1054 inp_locally_locked = 1; 1055 } 1056 1057 /* Find the TCP control block that corresponds with this packet. */ 1058 tp = intotcpcb(inp); 1059 1060 /* 1061 * If we can't find the TCP control block (happens occasionaly for a 1062 * packet sent during the shutdown phase of a TCP connection), 1063 * or we're in the timewait state, bail. 1064 */ 1065 if (tp == NULL || inp->inp_flags & INP_TIMEWAIT) { 1066 if (dir == PFIL_IN) 1067 ss->nskip_in_tcpcb++; 1068 else 1069 ss->nskip_out_tcpcb++; 1070 1071 goto inp_unlock6; 1072 } 1073 1074 pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO); 1075 1076 if (pn == NULL) { 1077 if (dir == PFIL_IN) 1078 ss->nskip_in_malloc++; 1079 else 1080 ss->nskip_out_malloc++; 1081 1082 goto inp_unlock6; 1083 } 1084 1085 siftr_siftdata(pn, inp, tp, INP_IPV6, dir, inp_locally_locked); 1086 1087 /* XXX: Figure out how to generate hashes for IPv6 packets. */ 1088 1089 mtx_lock(&siftr_pkt_queue_mtx); 1090 STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes); 1091 mtx_unlock(&siftr_pkt_queue_mtx); 1092 goto ret6; 1093 1094 inp_unlock6: 1095 if (inp_locally_locked) 1096 INP_RUNLOCK(inp); 1097 1098 ret6: 1099 /* Returning 0 ensures pfil will not discard the pkt. */ 1100 return (0); 1101 } 1102 #endif /* #ifdef SIFTR_IPV6 */ 1103 1104 1105 static int 1106 siftr_pfil(int action) 1107 { 1108 struct pfil_head *pfh_inet; 1109 #ifdef SIFTR_IPV6 1110 struct pfil_head *pfh_inet6; 1111 #endif 1112 VNET_ITERATOR_DECL(vnet_iter); 1113 1114 VNET_LIST_RLOCK(); 1115 VNET_FOREACH(vnet_iter) { 1116 CURVNET_SET(vnet_iter); 1117 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET); 1118 #ifdef SIFTR_IPV6 1119 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6); 1120 #endif 1121 1122 if (action == HOOK) { 1123 pfil_add_hook(siftr_chkpkt, NULL, 1124 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet); 1125 #ifdef SIFTR_IPV6 1126 pfil_add_hook(siftr_chkpkt6, NULL, 1127 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet6); 1128 #endif 1129 } else if (action == UNHOOK) { 1130 pfil_remove_hook(siftr_chkpkt, NULL, 1131 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet); 1132 #ifdef SIFTR_IPV6 1133 pfil_remove_hook(siftr_chkpkt6, NULL, 1134 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet6); 1135 #endif 1136 } 1137 CURVNET_RESTORE(); 1138 } 1139 VNET_LIST_RUNLOCK(); 1140 1141 return (0); 1142 } 1143 1144 1145 static int 1146 siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS) 1147 { 1148 struct alq *new_alq; 1149 int error; 1150 1151 if (req->newptr == NULL) 1152 goto skip; 1153 1154 /* If old filename and new filename are different. */ 1155 if (strncmp(siftr_logfile, (char *)req->newptr, PATH_MAX)) { 1156 1157 error = alq_open(&new_alq, req->newptr, curthread->td_ucred, 1158 SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0); 1159 1160 /* Bail if unable to create new alq. */ 1161 if (error) 1162 return (1); 1163 1164 /* 1165 * If disabled, siftr_alq == NULL so we simply close 1166 * the alq as we've proved it can be opened. 1167 * If enabled, close the existing alq and switch the old 1168 * for the new. 1169 */ 1170 if (siftr_alq == NULL) 1171 alq_close(new_alq); 1172 else { 1173 alq_close(siftr_alq); 1174 siftr_alq = new_alq; 1175 } 1176 } 1177 1178 skip: 1179 return (sysctl_handle_string(oidp, arg1, arg2, req)); 1180 } 1181 1182 1183 static int 1184 siftr_manage_ops(uint8_t action) 1185 { 1186 struct siftr_stats totalss; 1187 struct timeval tval; 1188 struct flow_hash_node *counter, *tmp_counter; 1189 struct sbuf *s; 1190 int i, key_index, ret, error; 1191 uint32_t bytes_to_write, total_skipped_pkts; 1192 uint16_t lport, fport; 1193 uint8_t *key, ipver; 1194 1195 #ifdef SIFTR_IPV6 1196 uint32_t laddr[4]; 1197 uint32_t faddr[4]; 1198 #else 1199 uint8_t laddr[4]; 1200 uint8_t faddr[4]; 1201 #endif 1202 1203 error = 0; 1204 total_skipped_pkts = 0; 1205 1206 /* Init an autosizing sbuf that initially holds 200 chars. */ 1207 if ((s = sbuf_new(NULL, NULL, 200, SBUF_AUTOEXTEND)) == NULL) 1208 return (-1); 1209 1210 if (action == SIFTR_ENABLE) { 1211 /* 1212 * Create our alq 1213 * XXX: We should abort if alq_open fails! 1214 */ 1215 alq_open(&siftr_alq, siftr_logfile, curthread->td_ucred, 1216 SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0); 1217 1218 STAILQ_INIT(&pkt_queue); 1219 1220 DPCPU_ZERO(ss); 1221 1222 siftr_exit_pkt_manager_thread = 0; 1223 1224 ret = kthread_add(&siftr_pkt_manager_thread, NULL, NULL, 1225 &siftr_pkt_manager_thr, RFNOWAIT, 0, 1226 "siftr_pkt_manager_thr"); 1227 1228 siftr_pfil(HOOK); 1229 1230 microtime(&tval); 1231 1232 sbuf_printf(s, 1233 "enable_time_secs=%jd\tenable_time_usecs=%06ld\t" 1234 "siftrver=%s\thz=%u\ttcp_rtt_scale=%u\tsysname=%s\t" 1235 "sysver=%u\tipmode=%u\n", 1236 (intmax_t)tval.tv_sec, tval.tv_usec, MODVERSION_STR, hz, 1237 TCP_RTT_SCALE, SYS_NAME, __FreeBSD_version, SIFTR_IPMODE); 1238 1239 sbuf_finish(s); 1240 alq_writen(siftr_alq, sbuf_data(s), sbuf_len(s), ALQ_WAITOK); 1241 1242 } else if (action == SIFTR_DISABLE && siftr_pkt_manager_thr != NULL) { 1243 /* 1244 * Remove the pfil hook functions. All threads currently in 1245 * the hook functions are allowed to exit before siftr_pfil() 1246 * returns. 1247 */ 1248 siftr_pfil(UNHOOK); 1249 1250 /* This will block until the pkt manager thread unlocks it. */ 1251 mtx_lock(&siftr_pkt_mgr_mtx); 1252 1253 /* Tell the pkt manager thread that it should exit now. */ 1254 siftr_exit_pkt_manager_thread = 1; 1255 1256 /* 1257 * Wake the pkt_manager thread so it realises that 1258 * siftr_exit_pkt_manager_thread == 1 and exits gracefully. 1259 * The wakeup won't be delivered until we unlock 1260 * siftr_pkt_mgr_mtx so this isn't racy. 1261 */ 1262 wakeup(&wait_for_pkt); 1263 1264 /* Wait for the pkt_manager thread to exit. */ 1265 mtx_sleep(siftr_pkt_manager_thr, &siftr_pkt_mgr_mtx, PWAIT, 1266 "thrwait", 0); 1267 1268 siftr_pkt_manager_thr = NULL; 1269 mtx_unlock(&siftr_pkt_mgr_mtx); 1270 1271 totalss.n_in = DPCPU_VARSUM(ss, n_in); 1272 totalss.n_out = DPCPU_VARSUM(ss, n_out); 1273 totalss.nskip_in_malloc = DPCPU_VARSUM(ss, nskip_in_malloc); 1274 totalss.nskip_out_malloc = DPCPU_VARSUM(ss, nskip_out_malloc); 1275 totalss.nskip_in_mtx = DPCPU_VARSUM(ss, nskip_in_mtx); 1276 totalss.nskip_out_mtx = DPCPU_VARSUM(ss, nskip_out_mtx); 1277 totalss.nskip_in_tcpcb = DPCPU_VARSUM(ss, nskip_in_tcpcb); 1278 totalss.nskip_out_tcpcb = DPCPU_VARSUM(ss, nskip_out_tcpcb); 1279 totalss.nskip_in_inpcb = DPCPU_VARSUM(ss, nskip_in_inpcb); 1280 totalss.nskip_out_inpcb = DPCPU_VARSUM(ss, nskip_out_inpcb); 1281 1282 total_skipped_pkts = totalss.nskip_in_malloc + 1283 totalss.nskip_out_malloc + totalss.nskip_in_mtx + 1284 totalss.nskip_out_mtx + totalss.nskip_in_tcpcb + 1285 totalss.nskip_out_tcpcb + totalss.nskip_in_inpcb + 1286 totalss.nskip_out_inpcb; 1287 1288 microtime(&tval); 1289 1290 sbuf_printf(s, 1291 "disable_time_secs=%jd\tdisable_time_usecs=%06ld\t" 1292 "num_inbound_tcp_pkts=%ju\tnum_outbound_tcp_pkts=%ju\t" 1293 "total_tcp_pkts=%ju\tnum_inbound_skipped_pkts_malloc=%u\t" 1294 "num_outbound_skipped_pkts_malloc=%u\t" 1295 "num_inbound_skipped_pkts_mtx=%u\t" 1296 "num_outbound_skipped_pkts_mtx=%u\t" 1297 "num_inbound_skipped_pkts_tcpcb=%u\t" 1298 "num_outbound_skipped_pkts_tcpcb=%u\t" 1299 "num_inbound_skipped_pkts_inpcb=%u\t" 1300 "num_outbound_skipped_pkts_inpcb=%u\t" 1301 "total_skipped_tcp_pkts=%u\tflow_list=", 1302 (intmax_t)tval.tv_sec, 1303 tval.tv_usec, 1304 (uintmax_t)totalss.n_in, 1305 (uintmax_t)totalss.n_out, 1306 (uintmax_t)(totalss.n_in + totalss.n_out), 1307 totalss.nskip_in_malloc, 1308 totalss.nskip_out_malloc, 1309 totalss.nskip_in_mtx, 1310 totalss.nskip_out_mtx, 1311 totalss.nskip_in_tcpcb, 1312 totalss.nskip_out_tcpcb, 1313 totalss.nskip_in_inpcb, 1314 totalss.nskip_out_inpcb, 1315 total_skipped_pkts); 1316 1317 /* 1318 * Iterate over the flow hash, printing a summary of each 1319 * flow seen and freeing any malloc'd memory. 1320 * The hash consists of an array of LISTs (man 3 queue). 1321 */ 1322 for (i = 0; i < siftr_hashmask; i++) { 1323 LIST_FOREACH_SAFE(counter, counter_hash + i, nodes, 1324 tmp_counter) { 1325 key = counter->key; 1326 key_index = 1; 1327 1328 ipver = key[0]; 1329 1330 memcpy(laddr, key + key_index, sizeof(laddr)); 1331 key_index += sizeof(laddr); 1332 memcpy(&lport, key + key_index, sizeof(lport)); 1333 key_index += sizeof(lport); 1334 memcpy(faddr, key + key_index, sizeof(faddr)); 1335 key_index += sizeof(faddr); 1336 memcpy(&fport, key + key_index, sizeof(fport)); 1337 1338 #ifdef SIFTR_IPV6 1339 laddr[3] = ntohl(laddr[3]); 1340 faddr[3] = ntohl(faddr[3]); 1341 1342 if (ipver == INP_IPV6) { 1343 laddr[0] = ntohl(laddr[0]); 1344 laddr[1] = ntohl(laddr[1]); 1345 laddr[2] = ntohl(laddr[2]); 1346 faddr[0] = ntohl(faddr[0]); 1347 faddr[1] = ntohl(faddr[1]); 1348 faddr[2] = ntohl(faddr[2]); 1349 1350 sbuf_printf(s, 1351 "%x:%x:%x:%x:%x:%x:%x:%x;%u-" 1352 "%x:%x:%x:%x:%x:%x:%x:%x;%u,", 1353 UPPER_SHORT(laddr[0]), 1354 LOWER_SHORT(laddr[0]), 1355 UPPER_SHORT(laddr[1]), 1356 LOWER_SHORT(laddr[1]), 1357 UPPER_SHORT(laddr[2]), 1358 LOWER_SHORT(laddr[2]), 1359 UPPER_SHORT(laddr[3]), 1360 LOWER_SHORT(laddr[3]), 1361 ntohs(lport), 1362 UPPER_SHORT(faddr[0]), 1363 LOWER_SHORT(faddr[0]), 1364 UPPER_SHORT(faddr[1]), 1365 LOWER_SHORT(faddr[1]), 1366 UPPER_SHORT(faddr[2]), 1367 LOWER_SHORT(faddr[2]), 1368 UPPER_SHORT(faddr[3]), 1369 LOWER_SHORT(faddr[3]), 1370 ntohs(fport)); 1371 } else { 1372 laddr[0] = FIRST_OCTET(laddr[3]); 1373 laddr[1] = SECOND_OCTET(laddr[3]); 1374 laddr[2] = THIRD_OCTET(laddr[3]); 1375 laddr[3] = FOURTH_OCTET(laddr[3]); 1376 faddr[0] = FIRST_OCTET(faddr[3]); 1377 faddr[1] = SECOND_OCTET(faddr[3]); 1378 faddr[2] = THIRD_OCTET(faddr[3]); 1379 faddr[3] = FOURTH_OCTET(faddr[3]); 1380 #endif 1381 sbuf_printf(s, 1382 "%u.%u.%u.%u;%u-%u.%u.%u.%u;%u,", 1383 laddr[0], 1384 laddr[1], 1385 laddr[2], 1386 laddr[3], 1387 ntohs(lport), 1388 faddr[0], 1389 faddr[1], 1390 faddr[2], 1391 faddr[3], 1392 ntohs(fport)); 1393 #ifdef SIFTR_IPV6 1394 } 1395 #endif 1396 1397 free(counter, M_SIFTR_HASHNODE); 1398 } 1399 1400 LIST_INIT(counter_hash + i); 1401 } 1402 1403 sbuf_printf(s, "\n"); 1404 sbuf_finish(s); 1405 1406 i = 0; 1407 do { 1408 bytes_to_write = min(SIFTR_ALQ_BUFLEN, sbuf_len(s)-i); 1409 alq_writen(siftr_alq, sbuf_data(s)+i, bytes_to_write, ALQ_WAITOK); 1410 i += bytes_to_write; 1411 } while (i < sbuf_len(s)); 1412 1413 alq_close(siftr_alq); 1414 siftr_alq = NULL; 1415 } 1416 1417 sbuf_delete(s); 1418 1419 /* 1420 * XXX: Should be using ret to check if any functions fail 1421 * and set error appropriately 1422 */ 1423 1424 return (error); 1425 } 1426 1427 1428 static int 1429 siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS) 1430 { 1431 if (req->newptr == NULL) 1432 goto skip; 1433 1434 /* If the value passed in isn't 0 or 1, return an error. */ 1435 if (CAST_PTR_INT(req->newptr) != 0 && CAST_PTR_INT(req->newptr) != 1) 1436 return (1); 1437 1438 /* If we are changing state (0 to 1 or 1 to 0). */ 1439 if (CAST_PTR_INT(req->newptr) != siftr_enabled ) 1440 if (siftr_manage_ops(CAST_PTR_INT(req->newptr))) { 1441 siftr_manage_ops(SIFTR_DISABLE); 1442 return (1); 1443 } 1444 1445 skip: 1446 return (sysctl_handle_int(oidp, arg1, arg2, req)); 1447 } 1448 1449 1450 static void 1451 siftr_shutdown_handler(void *arg) 1452 { 1453 siftr_manage_ops(SIFTR_DISABLE); 1454 } 1455 1456 1457 /* 1458 * Module is being unloaded or machine is shutting down. Take care of cleanup. 1459 */ 1460 static int 1461 deinit_siftr(void) 1462 { 1463 /* Cleanup. */ 1464 siftr_manage_ops(SIFTR_DISABLE); 1465 hashdestroy(counter_hash, M_SIFTR, siftr_hashmask); 1466 mtx_destroy(&siftr_pkt_queue_mtx); 1467 mtx_destroy(&siftr_pkt_mgr_mtx); 1468 1469 return (0); 1470 } 1471 1472 1473 /* 1474 * Module has just been loaded into the kernel. 1475 */ 1476 static int 1477 init_siftr(void) 1478 { 1479 EVENTHANDLER_REGISTER(shutdown_pre_sync, siftr_shutdown_handler, NULL, 1480 SHUTDOWN_PRI_FIRST); 1481 1482 /* Initialise our flow counter hash table. */ 1483 counter_hash = hashinit(SIFTR_EXPECTED_MAX_TCP_FLOWS, M_SIFTR, 1484 &siftr_hashmask); 1485 1486 mtx_init(&siftr_pkt_queue_mtx, "siftr_pkt_queue_mtx", NULL, MTX_DEF); 1487 mtx_init(&siftr_pkt_mgr_mtx, "siftr_pkt_mgr_mtx", NULL, MTX_DEF); 1488 1489 /* Print message to the user's current terminal. */ 1490 uprintf("\nStatistical Information For TCP Research (SIFTR) %s\n" 1491 " http://caia.swin.edu.au/urp/newtcp\n\n", 1492 MODVERSION_STR); 1493 1494 return (0); 1495 } 1496 1497 1498 /* 1499 * This is the function that is called to load and unload the module. 1500 * When the module is loaded, this function is called once with 1501 * "what" == MOD_LOAD 1502 * When the module is unloaded, this function is called twice with 1503 * "what" = MOD_QUIESCE first, followed by "what" = MOD_UNLOAD second 1504 * When the system is shut down e.g. CTRL-ALT-DEL or using the shutdown command, 1505 * this function is called once with "what" = MOD_SHUTDOWN 1506 * When the system is shut down, the handler isn't called until the very end 1507 * of the shutdown sequence i.e. after the disks have been synced. 1508 */ 1509 static int 1510 siftr_load_handler(module_t mod, int what, void *arg) 1511 { 1512 int ret; 1513 1514 switch (what) { 1515 case MOD_LOAD: 1516 ret = init_siftr(); 1517 break; 1518 1519 case MOD_QUIESCE: 1520 case MOD_SHUTDOWN: 1521 ret = deinit_siftr(); 1522 break; 1523 1524 case MOD_UNLOAD: 1525 ret = 0; 1526 break; 1527 1528 default: 1529 ret = EINVAL; 1530 break; 1531 } 1532 1533 return (ret); 1534 } 1535 1536 1537 static moduledata_t siftr_mod = { 1538 .name = "siftr", 1539 .evhand = siftr_load_handler, 1540 }; 1541 1542 /* 1543 * Param 1: name of the kernel module 1544 * Param 2: moduledata_t struct containing info about the kernel module 1545 * and the execution entry point for the module 1546 * Param 3: From sysinit_sub_id enumeration in /usr/include/sys/kernel.h 1547 * Defines the module initialisation order 1548 * Param 4: From sysinit_elem_order enumeration in /usr/include/sys/kernel.h 1549 * Defines the initialisation order of this kld relative to others 1550 * within the same subsystem as defined by param 3 1551 */ 1552 DECLARE_MODULE(siftr, siftr_mod, SI_SUB_SMP, SI_ORDER_ANY); 1553 MODULE_DEPEND(siftr, alq, 1, 1, 1); 1554 MODULE_VERSION(siftr, MODVERSION); 1555