FreeBSD/Linux Kernel Cross Reference
sys/netinet/siftr.c
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: releng/10.2/sys/netinet/siftr.c 281174 2015-04-06 22:41:13Z hiren $");
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 /* Flowid for the connection. */
229 u_int flowid;
230 /* Flow type for the connection. */
231 u_int flowtype;
232 /* Link to next pkt_node in the list. */
233 STAILQ_ENTRY(pkt_node) nodes;
234 };
235
236 struct flow_hash_node
237 {
238 uint16_t counter;
239 uint8_t key[FLOW_KEY_LEN];
240 LIST_ENTRY(flow_hash_node) nodes;
241 };
242
243 struct siftr_stats
244 {
245 /* # TCP pkts seen by the SIFTR PFIL hooks, including any skipped. */
246 uint64_t n_in;
247 uint64_t n_out;
248 /* # pkts skipped due to failed malloc calls. */
249 uint32_t nskip_in_malloc;
250 uint32_t nskip_out_malloc;
251 /* # pkts skipped due to failed mtx acquisition. */
252 uint32_t nskip_in_mtx;
253 uint32_t nskip_out_mtx;
254 /* # pkts skipped due to failed inpcb lookups. */
255 uint32_t nskip_in_inpcb;
256 uint32_t nskip_out_inpcb;
257 /* # pkts skipped due to failed tcpcb lookups. */
258 uint32_t nskip_in_tcpcb;
259 uint32_t nskip_out_tcpcb;
260 /* # pkts skipped due to stack reinjection. */
261 uint32_t nskip_in_dejavu;
262 uint32_t nskip_out_dejavu;
263 };
264
265 static DPCPU_DEFINE(struct siftr_stats, ss);
266
267 static volatile unsigned int siftr_exit_pkt_manager_thread = 0;
268 static unsigned int siftr_enabled = 0;
269 static unsigned int siftr_pkts_per_log = 1;
270 static unsigned int siftr_generate_hashes = 0;
271 /* static unsigned int siftr_binary_log = 0; */
272 static char siftr_logfile[PATH_MAX] = "/var/log/siftr.log";
273 static char siftr_logfile_shadow[PATH_MAX] = "/var/log/siftr.log";
274 static u_long siftr_hashmask;
275 STAILQ_HEAD(pkthead, pkt_node) pkt_queue = STAILQ_HEAD_INITIALIZER(pkt_queue);
276 LIST_HEAD(listhead, flow_hash_node) *counter_hash;
277 static int wait_for_pkt;
278 static struct alq *siftr_alq = NULL;
279 static struct mtx siftr_pkt_queue_mtx;
280 static struct mtx siftr_pkt_mgr_mtx;
281 static struct thread *siftr_pkt_manager_thr = NULL;
282 /*
283 * pfil.h defines PFIL_IN as 1 and PFIL_OUT as 2,
284 * which we use as an index into this array.
285 */
286 static char direction[3] = {'\0', 'i','o'};
287
288 /* Required function prototypes. */
289 static int siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS);
290 static int siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS);
291
292
293 /* Declare the net.inet.siftr sysctl tree and populate it. */
294
295 SYSCTL_DECL(_net_inet_siftr);
296
297 SYSCTL_NODE(_net_inet, OID_AUTO, siftr, CTLFLAG_RW, NULL,
298 "siftr related settings");
299
300 SYSCTL_PROC(_net_inet_siftr, OID_AUTO, enabled, CTLTYPE_UINT|CTLFLAG_RW,
301 &siftr_enabled, 0, &siftr_sysctl_enabled_handler, "IU",
302 "switch siftr module operations on/off");
303
304 SYSCTL_PROC(_net_inet_siftr, OID_AUTO, logfile, CTLTYPE_STRING|CTLFLAG_RW,
305 &siftr_logfile_shadow, sizeof(siftr_logfile_shadow), &siftr_sysctl_logfile_name_handler,
306 "A", "file to save siftr log messages to");
307
308 SYSCTL_UINT(_net_inet_siftr, OID_AUTO, ppl, CTLFLAG_RW,
309 &siftr_pkts_per_log, 1,
310 "number of packets between generating a log message");
311
312 SYSCTL_UINT(_net_inet_siftr, OID_AUTO, genhashes, CTLFLAG_RW,
313 &siftr_generate_hashes, 0,
314 "enable packet hash generation");
315
316 /* XXX: TODO
317 SYSCTL_UINT(_net_inet_siftr, OID_AUTO, binary, CTLFLAG_RW,
318 &siftr_binary_log, 0,
319 "write log files in binary instead of ascii");
320 */
321
322
323 /* Begin functions. */
324
325 static void
326 siftr_process_pkt(struct pkt_node * pkt_node)
327 {
328 struct flow_hash_node *hash_node;
329 struct listhead *counter_list;
330 struct siftr_stats *ss;
331 struct ale *log_buf;
332 uint8_t key[FLOW_KEY_LEN];
333 uint8_t found_match, key_offset;
334
335 hash_node = NULL;
336 ss = DPCPU_PTR(ss);
337 found_match = 0;
338 key_offset = 1;
339
340 /*
341 * Create the key that will be used to create a hash index
342 * into our hash table. Our key consists of:
343 * ipversion, localip, localport, foreignip, foreignport
344 */
345 key[0] = pkt_node->ipver;
346 memcpy(key + key_offset, &pkt_node->ip_laddr,
347 sizeof(pkt_node->ip_laddr));
348 key_offset += sizeof(pkt_node->ip_laddr);
349 memcpy(key + key_offset, &pkt_node->tcp_localport,
350 sizeof(pkt_node->tcp_localport));
351 key_offset += sizeof(pkt_node->tcp_localport);
352 memcpy(key + key_offset, &pkt_node->ip_faddr,
353 sizeof(pkt_node->ip_faddr));
354 key_offset += sizeof(pkt_node->ip_faddr);
355 memcpy(key + key_offset, &pkt_node->tcp_foreignport,
356 sizeof(pkt_node->tcp_foreignport));
357
358 counter_list = counter_hash +
359 (hash32_buf(key, sizeof(key), 0) & siftr_hashmask);
360
361 /*
362 * If the list is not empty i.e. the hash index has
363 * been used by another flow previously.
364 */
365 if (LIST_FIRST(counter_list) != NULL) {
366 /*
367 * Loop through the hash nodes in the list.
368 * There should normally only be 1 hash node in the list,
369 * except if there have been collisions at the hash index
370 * computed by hash32_buf().
371 */
372 LIST_FOREACH(hash_node, counter_list, nodes) {
373 /*
374 * Check if the key for the pkt we are currently
375 * processing is the same as the key stored in the
376 * hash node we are currently processing.
377 * If they are the same, then we've found the
378 * hash node that stores the counter for the flow
379 * the pkt belongs to.
380 */
381 if (memcmp(hash_node->key, key, sizeof(key)) == 0) {
382 found_match = 1;
383 break;
384 }
385 }
386 }
387
388 /* If this flow hash hasn't been seen before or we have a collision. */
389 if (hash_node == NULL || !found_match) {
390 /* Create a new hash node to store the flow's counter. */
391 hash_node = malloc(sizeof(struct flow_hash_node),
392 M_SIFTR_HASHNODE, M_WAITOK);
393
394 if (hash_node != NULL) {
395 /* Initialise our new hash node list entry. */
396 hash_node->counter = 0;
397 memcpy(hash_node->key, key, sizeof(key));
398 LIST_INSERT_HEAD(counter_list, hash_node, nodes);
399 } else {
400 /* Malloc failed. */
401 if (pkt_node->direction == PFIL_IN)
402 ss->nskip_in_malloc++;
403 else
404 ss->nskip_out_malloc++;
405
406 return;
407 }
408 } else if (siftr_pkts_per_log > 1) {
409 /*
410 * Taking the remainder of the counter divided
411 * by the current value of siftr_pkts_per_log
412 * and storing that in counter provides a neat
413 * way to modulate the frequency of log
414 * messages being written to the log file.
415 */
416 hash_node->counter = (hash_node->counter + 1) %
417 siftr_pkts_per_log;
418
419 /*
420 * If we have not seen enough packets since the last time
421 * we wrote a log message for this connection, return.
422 */
423 if (hash_node->counter > 0)
424 return;
425 }
426
427 log_buf = alq_getn(siftr_alq, MAX_LOG_MSG_LEN, ALQ_WAITOK);
428
429 if (log_buf == NULL)
430 return; /* Should only happen if the ALQ is shutting down. */
431
432 #ifdef SIFTR_IPV6
433 pkt_node->ip_laddr[3] = ntohl(pkt_node->ip_laddr[3]);
434 pkt_node->ip_faddr[3] = ntohl(pkt_node->ip_faddr[3]);
435
436 if (pkt_node->ipver == INP_IPV6) { /* IPv6 packet */
437 pkt_node->ip_laddr[0] = ntohl(pkt_node->ip_laddr[0]);
438 pkt_node->ip_laddr[1] = ntohl(pkt_node->ip_laddr[1]);
439 pkt_node->ip_laddr[2] = ntohl(pkt_node->ip_laddr[2]);
440 pkt_node->ip_faddr[0] = ntohl(pkt_node->ip_faddr[0]);
441 pkt_node->ip_faddr[1] = ntohl(pkt_node->ip_faddr[1]);
442 pkt_node->ip_faddr[2] = ntohl(pkt_node->ip_faddr[2]);
443
444 /* Construct an IPv6 log message. */
445 log_buf->ae_bytesused = snprintf(log_buf->ae_data,
446 MAX_LOG_MSG_LEN,
447 "%c,0x%08x,%zd.%06ld,%x:%x:%x:%x:%x:%x:%x:%x,%u,%x:%x:%x:"
448 "%x:%x:%x:%x:%x,%u,%ld,%ld,%ld,%ld,%ld,%u,%u,%u,%u,%u,%u,"
449 "%u,%d,%u,%u,%u,%u,%u,%u,%u,%u\n",
450 direction[pkt_node->direction],
451 pkt_node->hash,
452 pkt_node->tval.tv_sec,
453 pkt_node->tval.tv_usec,
454 UPPER_SHORT(pkt_node->ip_laddr[0]),
455 LOWER_SHORT(pkt_node->ip_laddr[0]),
456 UPPER_SHORT(pkt_node->ip_laddr[1]),
457 LOWER_SHORT(pkt_node->ip_laddr[1]),
458 UPPER_SHORT(pkt_node->ip_laddr[2]),
459 LOWER_SHORT(pkt_node->ip_laddr[2]),
460 UPPER_SHORT(pkt_node->ip_laddr[3]),
461 LOWER_SHORT(pkt_node->ip_laddr[3]),
462 ntohs(pkt_node->tcp_localport),
463 UPPER_SHORT(pkt_node->ip_faddr[0]),
464 LOWER_SHORT(pkt_node->ip_faddr[0]),
465 UPPER_SHORT(pkt_node->ip_faddr[1]),
466 LOWER_SHORT(pkt_node->ip_faddr[1]),
467 UPPER_SHORT(pkt_node->ip_faddr[2]),
468 LOWER_SHORT(pkt_node->ip_faddr[2]),
469 UPPER_SHORT(pkt_node->ip_faddr[3]),
470 LOWER_SHORT(pkt_node->ip_faddr[3]),
471 ntohs(pkt_node->tcp_foreignport),
472 pkt_node->snd_ssthresh,
473 pkt_node->snd_cwnd,
474 pkt_node->snd_bwnd,
475 pkt_node->snd_wnd,
476 pkt_node->rcv_wnd,
477 pkt_node->snd_scale,
478 pkt_node->rcv_scale,
479 pkt_node->conn_state,
480 pkt_node->max_seg_size,
481 pkt_node->smoothed_rtt,
482 pkt_node->sack_enabled,
483 pkt_node->flags,
484 pkt_node->rxt_length,
485 pkt_node->snd_buf_hiwater,
486 pkt_node->snd_buf_cc,
487 pkt_node->rcv_buf_hiwater,
488 pkt_node->rcv_buf_cc,
489 pkt_node->sent_inflight_bytes,
490 pkt_node->t_segqlen,
491 pkt_node->flowid,
492 pkt_node->flowtype);
493 } else { /* IPv4 packet */
494 pkt_node->ip_laddr[0] = FIRST_OCTET(pkt_node->ip_laddr[3]);
495 pkt_node->ip_laddr[1] = SECOND_OCTET(pkt_node->ip_laddr[3]);
496 pkt_node->ip_laddr[2] = THIRD_OCTET(pkt_node->ip_laddr[3]);
497 pkt_node->ip_laddr[3] = FOURTH_OCTET(pkt_node->ip_laddr[3]);
498 pkt_node->ip_faddr[0] = FIRST_OCTET(pkt_node->ip_faddr[3]);
499 pkt_node->ip_faddr[1] = SECOND_OCTET(pkt_node->ip_faddr[3]);
500 pkt_node->ip_faddr[2] = THIRD_OCTET(pkt_node->ip_faddr[3]);
501 pkt_node->ip_faddr[3] = FOURTH_OCTET(pkt_node->ip_faddr[3]);
502 #endif /* SIFTR_IPV6 */
503
504 /* Construct an IPv4 log message. */
505 log_buf->ae_bytesused = snprintf(log_buf->ae_data,
506 MAX_LOG_MSG_LEN,
507 "%c,0x%08x,%jd.%06ld,%u.%u.%u.%u,%u,%u.%u.%u.%u,%u,%ld,%ld,"
508 "%ld,%ld,%ld,%u,%u,%u,%u,%u,%u,%u,%d,%u,%u,%u,%u,%u,%u,%u,%u\n",
509 direction[pkt_node->direction],
510 pkt_node->hash,
511 (intmax_t)pkt_node->tval.tv_sec,
512 pkt_node->tval.tv_usec,
513 pkt_node->ip_laddr[0],
514 pkt_node->ip_laddr[1],
515 pkt_node->ip_laddr[2],
516 pkt_node->ip_laddr[3],
517 ntohs(pkt_node->tcp_localport),
518 pkt_node->ip_faddr[0],
519 pkt_node->ip_faddr[1],
520 pkt_node->ip_faddr[2],
521 pkt_node->ip_faddr[3],
522 ntohs(pkt_node->tcp_foreignport),
523 pkt_node->snd_ssthresh,
524 pkt_node->snd_cwnd,
525 pkt_node->snd_bwnd,
526 pkt_node->snd_wnd,
527 pkt_node->rcv_wnd,
528 pkt_node->snd_scale,
529 pkt_node->rcv_scale,
530 pkt_node->conn_state,
531 pkt_node->max_seg_size,
532 pkt_node->smoothed_rtt,
533 pkt_node->sack_enabled,
534 pkt_node->flags,
535 pkt_node->rxt_length,
536 pkt_node->snd_buf_hiwater,
537 pkt_node->snd_buf_cc,
538 pkt_node->rcv_buf_hiwater,
539 pkt_node->rcv_buf_cc,
540 pkt_node->sent_inflight_bytes,
541 pkt_node->t_segqlen,
542 pkt_node->flowid,
543 pkt_node->flowtype);
544 #ifdef SIFTR_IPV6
545 }
546 #endif
547
548 alq_post_flags(siftr_alq, log_buf, 0);
549 }
550
551
552 static void
553 siftr_pkt_manager_thread(void *arg)
554 {
555 STAILQ_HEAD(pkthead, pkt_node) tmp_pkt_queue =
556 STAILQ_HEAD_INITIALIZER(tmp_pkt_queue);
557 struct pkt_node *pkt_node, *pkt_node_temp;
558 uint8_t draining;
559
560 draining = 2;
561
562 mtx_lock(&siftr_pkt_mgr_mtx);
563
564 /* draining == 0 when queue has been flushed and it's safe to exit. */
565 while (draining) {
566 /*
567 * Sleep until we are signalled to wake because thread has
568 * been told to exit or until 1 tick has passed.
569 */
570 mtx_sleep(&wait_for_pkt, &siftr_pkt_mgr_mtx, PWAIT, "pktwait",
571 1);
572
573 /* Gain exclusive access to the pkt_node queue. */
574 mtx_lock(&siftr_pkt_queue_mtx);
575
576 /*
577 * Move pkt_queue to tmp_pkt_queue, which leaves
578 * pkt_queue empty and ready to receive more pkt_nodes.
579 */
580 STAILQ_CONCAT(&tmp_pkt_queue, &pkt_queue);
581
582 /*
583 * We've finished making changes to the list. Unlock it
584 * so the pfil hooks can continue queuing pkt_nodes.
585 */
586 mtx_unlock(&siftr_pkt_queue_mtx);
587
588 /*
589 * We can't hold a mutex whilst calling siftr_process_pkt
590 * because ALQ might sleep waiting for buffer space.
591 */
592 mtx_unlock(&siftr_pkt_mgr_mtx);
593
594 /* Flush all pkt_nodes to the log file. */
595 STAILQ_FOREACH_SAFE(pkt_node, &tmp_pkt_queue, nodes,
596 pkt_node_temp) {
597 siftr_process_pkt(pkt_node);
598 STAILQ_REMOVE_HEAD(&tmp_pkt_queue, nodes);
599 free(pkt_node, M_SIFTR_PKTNODE);
600 }
601
602 KASSERT(STAILQ_EMPTY(&tmp_pkt_queue),
603 ("SIFTR tmp_pkt_queue not empty after flush"));
604
605 mtx_lock(&siftr_pkt_mgr_mtx);
606
607 /*
608 * If siftr_exit_pkt_manager_thread gets set during the window
609 * where we are draining the tmp_pkt_queue above, there might
610 * still be pkts in pkt_queue that need to be drained.
611 * Allow one further iteration to occur after
612 * siftr_exit_pkt_manager_thread has been set to ensure
613 * pkt_queue is completely empty before we kill the thread.
614 *
615 * siftr_exit_pkt_manager_thread is set only after the pfil
616 * hooks have been removed, so only 1 extra iteration
617 * is needed to drain the queue.
618 */
619 if (siftr_exit_pkt_manager_thread)
620 draining--;
621 }
622
623 mtx_unlock(&siftr_pkt_mgr_mtx);
624
625 /* Calls wakeup on this thread's struct thread ptr. */
626 kthread_exit();
627 }
628
629
630 static uint32_t
631 hash_pkt(struct mbuf *m, uint32_t offset)
632 {
633 uint32_t hash;
634
635 hash = 0;
636
637 while (m != NULL && offset > m->m_len) {
638 /*
639 * The IP packet payload does not start in this mbuf, so
640 * need to figure out which mbuf it starts in and what offset
641 * into the mbuf's data region the payload starts at.
642 */
643 offset -= m->m_len;
644 m = m->m_next;
645 }
646
647 while (m != NULL) {
648 /* Ensure there is data in the mbuf */
649 if ((m->m_len - offset) > 0)
650 hash = hash32_buf(m->m_data + offset,
651 m->m_len - offset, hash);
652
653 m = m->m_next;
654 offset = 0;
655 }
656
657 return (hash);
658 }
659
660
661 /*
662 * Check if a given mbuf has the SIFTR mbuf tag. If it does, log the fact that
663 * it's a reinjected packet and return. If it doesn't, tag the mbuf and return.
664 * Return value >0 means the caller should skip processing this mbuf.
665 */
666 static inline int
667 siftr_chkreinject(struct mbuf *m, int dir, struct siftr_stats *ss)
668 {
669 if (m_tag_locate(m, PACKET_COOKIE_SIFTR, PACKET_TAG_SIFTR, NULL)
670 != NULL) {
671 if (dir == PFIL_IN)
672 ss->nskip_in_dejavu++;
673 else
674 ss->nskip_out_dejavu++;
675
676 return (1);
677 } else {
678 struct m_tag *tag = m_tag_alloc(PACKET_COOKIE_SIFTR,
679 PACKET_TAG_SIFTR, 0, M_NOWAIT);
680 if (tag == NULL) {
681 if (dir == PFIL_IN)
682 ss->nskip_in_malloc++;
683 else
684 ss->nskip_out_malloc++;
685
686 return (1);
687 }
688
689 m_tag_prepend(m, tag);
690 }
691
692 return (0);
693 }
694
695
696 /*
697 * Look up an inpcb for a packet. Return the inpcb pointer if found, or NULL
698 * otherwise.
699 */
700 static inline struct inpcb *
701 siftr_findinpcb(int ipver, struct ip *ip, struct mbuf *m, uint16_t sport,
702 uint16_t dport, int dir, struct siftr_stats *ss)
703 {
704 struct inpcb *inp;
705
706 /* We need the tcbinfo lock. */
707 INP_INFO_UNLOCK_ASSERT(&V_tcbinfo);
708
709 if (dir == PFIL_IN)
710 inp = (ipver == INP_IPV4 ?
711 in_pcblookup(&V_tcbinfo, ip->ip_src, sport, ip->ip_dst,
712 dport, INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif)
713 :
714 #ifdef SIFTR_IPV6
715 in6_pcblookup(&V_tcbinfo,
716 &((struct ip6_hdr *)ip)->ip6_src, sport,
717 &((struct ip6_hdr *)ip)->ip6_dst, dport, INPLOOKUP_RLOCKPCB,
718 m->m_pkthdr.rcvif)
719 #else
720 NULL
721 #endif
722 );
723
724 else
725 inp = (ipver == INP_IPV4 ?
726 in_pcblookup(&V_tcbinfo, ip->ip_dst, dport, ip->ip_src,
727 sport, INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif)
728 :
729 #ifdef SIFTR_IPV6
730 in6_pcblookup(&V_tcbinfo,
731 &((struct ip6_hdr *)ip)->ip6_dst, dport,
732 &((struct ip6_hdr *)ip)->ip6_src, sport, INPLOOKUP_RLOCKPCB,
733 m->m_pkthdr.rcvif)
734 #else
735 NULL
736 #endif
737 );
738
739 /* If we can't find the inpcb, bail. */
740 if (inp == NULL) {
741 if (dir == PFIL_IN)
742 ss->nskip_in_inpcb++;
743 else
744 ss->nskip_out_inpcb++;
745 }
746
747 return (inp);
748 }
749
750
751 static inline void
752 siftr_siftdata(struct pkt_node *pn, struct inpcb *inp, struct tcpcb *tp,
753 int ipver, int dir, int inp_locally_locked)
754 {
755 #ifdef SIFTR_IPV6
756 if (ipver == INP_IPV4) {
757 pn->ip_laddr[3] = inp->inp_laddr.s_addr;
758 pn->ip_faddr[3] = inp->inp_faddr.s_addr;
759 #else
760 *((uint32_t *)pn->ip_laddr) = inp->inp_laddr.s_addr;
761 *((uint32_t *)pn->ip_faddr) = inp->inp_faddr.s_addr;
762 #endif
763 #ifdef SIFTR_IPV6
764 } else {
765 pn->ip_laddr[0] = inp->in6p_laddr.s6_addr32[0];
766 pn->ip_laddr[1] = inp->in6p_laddr.s6_addr32[1];
767 pn->ip_laddr[2] = inp->in6p_laddr.s6_addr32[2];
768 pn->ip_laddr[3] = inp->in6p_laddr.s6_addr32[3];
769 pn->ip_faddr[0] = inp->in6p_faddr.s6_addr32[0];
770 pn->ip_faddr[1] = inp->in6p_faddr.s6_addr32[1];
771 pn->ip_faddr[2] = inp->in6p_faddr.s6_addr32[2];
772 pn->ip_faddr[3] = inp->in6p_faddr.s6_addr32[3];
773 }
774 #endif
775 pn->tcp_localport = inp->inp_lport;
776 pn->tcp_foreignport = inp->inp_fport;
777 pn->snd_cwnd = tp->snd_cwnd;
778 pn->snd_wnd = tp->snd_wnd;
779 pn->rcv_wnd = tp->rcv_wnd;
780 pn->snd_bwnd = 0; /* Unused, kept for compat. */
781 pn->snd_ssthresh = tp->snd_ssthresh;
782 pn->snd_scale = tp->snd_scale;
783 pn->rcv_scale = tp->rcv_scale;
784 pn->conn_state = tp->t_state;
785 pn->max_seg_size = tp->t_maxseg;
786 pn->smoothed_rtt = tp->t_srtt;
787 pn->sack_enabled = (tp->t_flags & TF_SACK_PERMIT) != 0;
788 pn->flags = tp->t_flags;
789 pn->rxt_length = tp->t_rxtcur;
790 pn->snd_buf_hiwater = inp->inp_socket->so_snd.sb_hiwat;
791 pn->snd_buf_cc = inp->inp_socket->so_snd.sb_cc;
792 pn->rcv_buf_hiwater = inp->inp_socket->so_rcv.sb_hiwat;
793 pn->rcv_buf_cc = inp->inp_socket->so_rcv.sb_cc;
794 pn->sent_inflight_bytes = tp->snd_max - tp->snd_una;
795 pn->t_segqlen = tp->t_segqlen;
796 pn->flowid = inp->inp_flowid;
797 pn->flowtype = inp->inp_flowtype;
798
799 /* We've finished accessing the tcb so release the lock. */
800 if (inp_locally_locked)
801 INP_RUNLOCK(inp);
802
803 pn->ipver = ipver;
804 pn->direction = dir;
805
806 /*
807 * Significantly more accurate than using getmicrotime(), but slower!
808 * Gives true microsecond resolution at the expense of a hit to
809 * maximum pps throughput processing when SIFTR is loaded and enabled.
810 */
811 microtime(&pn->tval);
812 }
813
814
815 /*
816 * pfil hook that is called for each IPv4 packet making its way through the
817 * stack in either direction.
818 * The pfil subsystem holds a non-sleepable mutex somewhere when
819 * calling our hook function, so we can't sleep at all.
820 * It's very important to use the M_NOWAIT flag with all function calls
821 * that support it so that they won't sleep, otherwise you get a panic.
822 */
823 static int
824 siftr_chkpkt(void *arg, struct mbuf **m, struct ifnet *ifp, int dir,
825 struct inpcb *inp)
826 {
827 struct pkt_node *pn;
828 struct ip *ip;
829 struct tcphdr *th;
830 struct tcpcb *tp;
831 struct siftr_stats *ss;
832 unsigned int ip_hl;
833 int inp_locally_locked;
834
835 inp_locally_locked = 0;
836 ss = DPCPU_PTR(ss);
837
838 /*
839 * m_pullup is not required here because ip_{input|output}
840 * already do the heavy lifting for us.
841 */
842
843 ip = mtod(*m, struct ip *);
844
845 /* Only continue processing if the packet is TCP. */
846 if (ip->ip_p != IPPROTO_TCP)
847 goto ret;
848
849 /*
850 * If a kernel subsystem reinjects packets into the stack, our pfil
851 * hook will be called multiple times for the same packet.
852 * Make sure we only process unique packets.
853 */
854 if (siftr_chkreinject(*m, dir, ss))
855 goto ret;
856
857 if (dir == PFIL_IN)
858 ss->n_in++;
859 else
860 ss->n_out++;
861
862 /*
863 * Create a tcphdr struct starting at the correct offset
864 * in the IP packet. ip->ip_hl gives the ip header length
865 * in 4-byte words, so multiply it to get the size in bytes.
866 */
867 ip_hl = (ip->ip_hl << 2);
868 th = (struct tcphdr *)((caddr_t)ip + ip_hl);
869
870 /*
871 * If the pfil hooks don't provide a pointer to the
872 * inpcb, we need to find it ourselves and lock it.
873 */
874 if (!inp) {
875 /* Find the corresponding inpcb for this pkt. */
876 inp = siftr_findinpcb(INP_IPV4, ip, *m, th->th_sport,
877 th->th_dport, dir, ss);
878
879 if (inp == NULL)
880 goto ret;
881 else
882 inp_locally_locked = 1;
883 }
884
885 INP_LOCK_ASSERT(inp);
886
887 /* Find the TCP control block that corresponds with this packet */
888 tp = intotcpcb(inp);
889
890 /*
891 * If we can't find the TCP control block (happens occasionaly for a
892 * packet sent during the shutdown phase of a TCP connection),
893 * or we're in the timewait state, bail
894 */
895 if (tp == NULL || inp->inp_flags & INP_TIMEWAIT) {
896 if (dir == PFIL_IN)
897 ss->nskip_in_tcpcb++;
898 else
899 ss->nskip_out_tcpcb++;
900
901 goto inp_unlock;
902 }
903
904 pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO);
905
906 if (pn == NULL) {
907 if (dir == PFIL_IN)
908 ss->nskip_in_malloc++;
909 else
910 ss->nskip_out_malloc++;
911
912 goto inp_unlock;
913 }
914
915 siftr_siftdata(pn, inp, tp, INP_IPV4, dir, inp_locally_locked);
916
917 if (siftr_generate_hashes) {
918 if ((*m)->m_pkthdr.csum_flags & CSUM_TCP) {
919 /*
920 * For outbound packets, the TCP checksum isn't
921 * calculated yet. This is a problem for our packet
922 * hashing as the receiver will calc a different hash
923 * to ours if we don't include the correct TCP checksum
924 * in the bytes being hashed. To work around this
925 * problem, we manually calc the TCP checksum here in
926 * software. We unset the CSUM_TCP flag so the lower
927 * layers don't recalc it.
928 */
929 (*m)->m_pkthdr.csum_flags &= ~CSUM_TCP;
930
931 /*
932 * Calculate the TCP checksum in software and assign
933 * to correct TCP header field, which will follow the
934 * packet mbuf down the stack. The trick here is that
935 * tcp_output() sets th->th_sum to the checksum of the
936 * pseudo header for us already. Because of the nature
937 * of the checksumming algorithm, we can sum over the
938 * entire IP payload (i.e. TCP header and data), which
939 * will include the already calculated pseduo header
940 * checksum, thus giving us the complete TCP checksum.
941 *
942 * To put it in simple terms, if checksum(1,2,3,4)=10,
943 * then checksum(1,2,3,4,5) == checksum(10,5).
944 * This property is what allows us to "cheat" and
945 * checksum only the IP payload which has the TCP
946 * th_sum field populated with the pseudo header's
947 * checksum, and not need to futz around checksumming
948 * pseudo header bytes and TCP header/data in one hit.
949 * Refer to RFC 1071 for more info.
950 *
951 * NB: in_cksum_skip(struct mbuf *m, int len, int skip)
952 * in_cksum_skip 2nd argument is NOT the number of
953 * bytes to read from the mbuf at "skip" bytes offset
954 * from the start of the mbuf (very counter intuitive!).
955 * The number of bytes to read is calculated internally
956 * by the function as len-skip i.e. to sum over the IP
957 * payload (TCP header + data) bytes, it is INCORRECT
958 * to call the function like this:
959 * in_cksum_skip(at, ip->ip_len - offset, offset)
960 * Rather, it should be called like this:
961 * in_cksum_skip(at, ip->ip_len, offset)
962 * which means read "ip->ip_len - offset" bytes from
963 * the mbuf cluster "at" at offset "offset" bytes from
964 * the beginning of the "at" mbuf's data pointer.
965 */
966 th->th_sum = in_cksum_skip(*m, ntohs(ip->ip_len),
967 ip_hl);
968 }
969
970 /*
971 * XXX: Having to calculate the checksum in software and then
972 * hash over all bytes is really inefficient. Would be nice to
973 * find a way to create the hash and checksum in the same pass
974 * over the bytes.
975 */
976 pn->hash = hash_pkt(*m, ip_hl);
977 }
978
979 mtx_lock(&siftr_pkt_queue_mtx);
980 STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes);
981 mtx_unlock(&siftr_pkt_queue_mtx);
982 goto ret;
983
984 inp_unlock:
985 if (inp_locally_locked)
986 INP_RUNLOCK(inp);
987
988 ret:
989 /* Returning 0 ensures pfil will not discard the pkt */
990 return (0);
991 }
992
993
994 #ifdef SIFTR_IPV6
995 static int
996 siftr_chkpkt6(void *arg, struct mbuf **m, struct ifnet *ifp, int dir,
997 struct inpcb *inp)
998 {
999 struct pkt_node *pn;
1000 struct ip6_hdr *ip6;
1001 struct tcphdr *th;
1002 struct tcpcb *tp;
1003 struct siftr_stats *ss;
1004 unsigned int ip6_hl;
1005 int inp_locally_locked;
1006
1007 inp_locally_locked = 0;
1008 ss = DPCPU_PTR(ss);
1009
1010 /*
1011 * m_pullup is not required here because ip6_{input|output}
1012 * already do the heavy lifting for us.
1013 */
1014
1015 ip6 = mtod(*m, struct ip6_hdr *);
1016
1017 /*
1018 * Only continue processing if the packet is TCP
1019 * XXX: We should follow the next header fields
1020 * as shown on Pg 6 RFC 2460, but right now we'll
1021 * only check pkts that have no extension headers.
1022 */
1023 if (ip6->ip6_nxt != IPPROTO_TCP)
1024 goto ret6;
1025
1026 /*
1027 * If a kernel subsystem reinjects packets into the stack, our pfil
1028 * hook will be called multiple times for the same packet.
1029 * Make sure we only process unique packets.
1030 */
1031 if (siftr_chkreinject(*m, dir, ss))
1032 goto ret6;
1033
1034 if (dir == PFIL_IN)
1035 ss->n_in++;
1036 else
1037 ss->n_out++;
1038
1039 ip6_hl = sizeof(struct ip6_hdr);
1040
1041 /*
1042 * Create a tcphdr struct starting at the correct offset
1043 * in the ipv6 packet. ip->ip_hl gives the ip header length
1044 * in 4-byte words, so multiply it to get the size in bytes.
1045 */
1046 th = (struct tcphdr *)((caddr_t)ip6 + ip6_hl);
1047
1048 /*
1049 * For inbound packets, the pfil hooks don't provide a pointer to the
1050 * inpcb, so we need to find it ourselves and lock it.
1051 */
1052 if (!inp) {
1053 /* Find the corresponding inpcb for this pkt. */
1054 inp = siftr_findinpcb(INP_IPV6, (struct ip *)ip6, *m,
1055 th->th_sport, th->th_dport, dir, ss);
1056
1057 if (inp == NULL)
1058 goto ret6;
1059 else
1060 inp_locally_locked = 1;
1061 }
1062
1063 /* Find the TCP control block that corresponds with this packet. */
1064 tp = intotcpcb(inp);
1065
1066 /*
1067 * If we can't find the TCP control block (happens occasionaly for a
1068 * packet sent during the shutdown phase of a TCP connection),
1069 * or we're in the timewait state, bail.
1070 */
1071 if (tp == NULL || inp->inp_flags & INP_TIMEWAIT) {
1072 if (dir == PFIL_IN)
1073 ss->nskip_in_tcpcb++;
1074 else
1075 ss->nskip_out_tcpcb++;
1076
1077 goto inp_unlock6;
1078 }
1079
1080 pn = malloc(sizeof(struct pkt_node), M_SIFTR_PKTNODE, M_NOWAIT|M_ZERO);
1081
1082 if (pn == NULL) {
1083 if (dir == PFIL_IN)
1084 ss->nskip_in_malloc++;
1085 else
1086 ss->nskip_out_malloc++;
1087
1088 goto inp_unlock6;
1089 }
1090
1091 siftr_siftdata(pn, inp, tp, INP_IPV6, dir, inp_locally_locked);
1092
1093 /* XXX: Figure out how to generate hashes for IPv6 packets. */
1094
1095 mtx_lock(&siftr_pkt_queue_mtx);
1096 STAILQ_INSERT_TAIL(&pkt_queue, pn, nodes);
1097 mtx_unlock(&siftr_pkt_queue_mtx);
1098 goto ret6;
1099
1100 inp_unlock6:
1101 if (inp_locally_locked)
1102 INP_RUNLOCK(inp);
1103
1104 ret6:
1105 /* Returning 0 ensures pfil will not discard the pkt. */
1106 return (0);
1107 }
1108 #endif /* #ifdef SIFTR_IPV6 */
1109
1110
1111 static int
1112 siftr_pfil(int action)
1113 {
1114 struct pfil_head *pfh_inet;
1115 #ifdef SIFTR_IPV6
1116 struct pfil_head *pfh_inet6;
1117 #endif
1118 VNET_ITERATOR_DECL(vnet_iter);
1119
1120 VNET_LIST_RLOCK();
1121 VNET_FOREACH(vnet_iter) {
1122 CURVNET_SET(vnet_iter);
1123 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
1124 #ifdef SIFTR_IPV6
1125 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
1126 #endif
1127
1128 if (action == HOOK) {
1129 pfil_add_hook(siftr_chkpkt, NULL,
1130 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet);
1131 #ifdef SIFTR_IPV6
1132 pfil_add_hook(siftr_chkpkt6, NULL,
1133 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet6);
1134 #endif
1135 } else if (action == UNHOOK) {
1136 pfil_remove_hook(siftr_chkpkt, NULL,
1137 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet);
1138 #ifdef SIFTR_IPV6
1139 pfil_remove_hook(siftr_chkpkt6, NULL,
1140 PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh_inet6);
1141 #endif
1142 }
1143 CURVNET_RESTORE();
1144 }
1145 VNET_LIST_RUNLOCK();
1146
1147 return (0);
1148 }
1149
1150
1151 static int
1152 siftr_sysctl_logfile_name_handler(SYSCTL_HANDLER_ARGS)
1153 {
1154 struct alq *new_alq;
1155 int error;
1156
1157 error = sysctl_handle_string(oidp, arg1, arg2, req);
1158
1159 /* Check for error or same filename */
1160 if (error != 0 || req->newptr == NULL ||
1161 strncmp(siftr_logfile, arg1, arg2) == 0)
1162 goto done;
1163
1164 /* Filname changed */
1165 error = alq_open(&new_alq, arg1, curthread->td_ucred,
1166 SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0);
1167 if (error != 0)
1168 goto done;
1169
1170 /*
1171 * If disabled, siftr_alq == NULL so we simply close
1172 * the alq as we've proved it can be opened.
1173 * If enabled, close the existing alq and switch the old
1174 * for the new.
1175 */
1176 if (siftr_alq == NULL) {
1177 alq_close(new_alq);
1178 } else {
1179 alq_close(siftr_alq);
1180 siftr_alq = new_alq;
1181 }
1182
1183 /* Update filename upon success */
1184 strlcpy(siftr_logfile, arg1, arg2);
1185 done:
1186 return (error);
1187 }
1188
1189 static int
1190 siftr_manage_ops(uint8_t action)
1191 {
1192 struct siftr_stats totalss;
1193 struct timeval tval;
1194 struct flow_hash_node *counter, *tmp_counter;
1195 struct sbuf *s;
1196 int i, key_index, ret, error;
1197 uint32_t bytes_to_write, total_skipped_pkts;
1198 uint16_t lport, fport;
1199 uint8_t *key, ipver;
1200
1201 #ifdef SIFTR_IPV6
1202 uint32_t laddr[4];
1203 uint32_t faddr[4];
1204 #else
1205 uint8_t laddr[4];
1206 uint8_t faddr[4];
1207 #endif
1208
1209 error = 0;
1210 total_skipped_pkts = 0;
1211
1212 /* Init an autosizing sbuf that initially holds 200 chars. */
1213 if ((s = sbuf_new(NULL, NULL, 200, SBUF_AUTOEXTEND)) == NULL)
1214 return (-1);
1215
1216 if (action == SIFTR_ENABLE) {
1217 /*
1218 * Create our alq
1219 * XXX: We should abort if alq_open fails!
1220 */
1221 alq_open(&siftr_alq, siftr_logfile, curthread->td_ucred,
1222 SIFTR_LOG_FILE_MODE, SIFTR_ALQ_BUFLEN, 0);
1223
1224 STAILQ_INIT(&pkt_queue);
1225
1226 DPCPU_ZERO(ss);
1227
1228 siftr_exit_pkt_manager_thread = 0;
1229
1230 ret = kthread_add(&siftr_pkt_manager_thread, NULL, NULL,
1231 &siftr_pkt_manager_thr, RFNOWAIT, 0,
1232 "siftr_pkt_manager_thr");
1233
1234 siftr_pfil(HOOK);
1235
1236 microtime(&tval);
1237
1238 sbuf_printf(s,
1239 "enable_time_secs=%jd\tenable_time_usecs=%06ld\t"
1240 "siftrver=%s\thz=%u\ttcp_rtt_scale=%u\tsysname=%s\t"
1241 "sysver=%u\tipmode=%u\n",
1242 (intmax_t)tval.tv_sec, tval.tv_usec, MODVERSION_STR, hz,
1243 TCP_RTT_SCALE, SYS_NAME, __FreeBSD_version, SIFTR_IPMODE);
1244
1245 sbuf_finish(s);
1246 alq_writen(siftr_alq, sbuf_data(s), sbuf_len(s), ALQ_WAITOK);
1247
1248 } else if (action == SIFTR_DISABLE && siftr_pkt_manager_thr != NULL) {
1249 /*
1250 * Remove the pfil hook functions. All threads currently in
1251 * the hook functions are allowed to exit before siftr_pfil()
1252 * returns.
1253 */
1254 siftr_pfil(UNHOOK);
1255
1256 /* This will block until the pkt manager thread unlocks it. */
1257 mtx_lock(&siftr_pkt_mgr_mtx);
1258
1259 /* Tell the pkt manager thread that it should exit now. */
1260 siftr_exit_pkt_manager_thread = 1;
1261
1262 /*
1263 * Wake the pkt_manager thread so it realises that
1264 * siftr_exit_pkt_manager_thread == 1 and exits gracefully.
1265 * The wakeup won't be delivered until we unlock
1266 * siftr_pkt_mgr_mtx so this isn't racy.
1267 */
1268 wakeup(&wait_for_pkt);
1269
1270 /* Wait for the pkt_manager thread to exit. */
1271 mtx_sleep(siftr_pkt_manager_thr, &siftr_pkt_mgr_mtx, PWAIT,
1272 "thrwait", 0);
1273
1274 siftr_pkt_manager_thr = NULL;
1275 mtx_unlock(&siftr_pkt_mgr_mtx);
1276
1277 totalss.n_in = DPCPU_VARSUM(ss, n_in);
1278 totalss.n_out = DPCPU_VARSUM(ss, n_out);
1279 totalss.nskip_in_malloc = DPCPU_VARSUM(ss, nskip_in_malloc);
1280 totalss.nskip_out_malloc = DPCPU_VARSUM(ss, nskip_out_malloc);
1281 totalss.nskip_in_mtx = DPCPU_VARSUM(ss, nskip_in_mtx);
1282 totalss.nskip_out_mtx = DPCPU_VARSUM(ss, nskip_out_mtx);
1283 totalss.nskip_in_tcpcb = DPCPU_VARSUM(ss, nskip_in_tcpcb);
1284 totalss.nskip_out_tcpcb = DPCPU_VARSUM(ss, nskip_out_tcpcb);
1285 totalss.nskip_in_inpcb = DPCPU_VARSUM(ss, nskip_in_inpcb);
1286 totalss.nskip_out_inpcb = DPCPU_VARSUM(ss, nskip_out_inpcb);
1287
1288 total_skipped_pkts = totalss.nskip_in_malloc +
1289 totalss.nskip_out_malloc + totalss.nskip_in_mtx +
1290 totalss.nskip_out_mtx + totalss.nskip_in_tcpcb +
1291 totalss.nskip_out_tcpcb + totalss.nskip_in_inpcb +
1292 totalss.nskip_out_inpcb;
1293
1294 microtime(&tval);
1295
1296 sbuf_printf(s,
1297 "disable_time_secs=%jd\tdisable_time_usecs=%06ld\t"
1298 "num_inbound_tcp_pkts=%ju\tnum_outbound_tcp_pkts=%ju\t"
1299 "total_tcp_pkts=%ju\tnum_inbound_skipped_pkts_malloc=%u\t"
1300 "num_outbound_skipped_pkts_malloc=%u\t"
1301 "num_inbound_skipped_pkts_mtx=%u\t"
1302 "num_outbound_skipped_pkts_mtx=%u\t"
1303 "num_inbound_skipped_pkts_tcpcb=%u\t"
1304 "num_outbound_skipped_pkts_tcpcb=%u\t"
1305 "num_inbound_skipped_pkts_inpcb=%u\t"
1306 "num_outbound_skipped_pkts_inpcb=%u\t"
1307 "total_skipped_tcp_pkts=%u\tflow_list=",
1308 (intmax_t)tval.tv_sec,
1309 tval.tv_usec,
1310 (uintmax_t)totalss.n_in,
1311 (uintmax_t)totalss.n_out,
1312 (uintmax_t)(totalss.n_in + totalss.n_out),
1313 totalss.nskip_in_malloc,
1314 totalss.nskip_out_malloc,
1315 totalss.nskip_in_mtx,
1316 totalss.nskip_out_mtx,
1317 totalss.nskip_in_tcpcb,
1318 totalss.nskip_out_tcpcb,
1319 totalss.nskip_in_inpcb,
1320 totalss.nskip_out_inpcb,
1321 total_skipped_pkts);
1322
1323 /*
1324 * Iterate over the flow hash, printing a summary of each
1325 * flow seen and freeing any malloc'd memory.
1326 * The hash consists of an array of LISTs (man 3 queue).
1327 */
1328 for (i = 0; i <= siftr_hashmask; i++) {
1329 LIST_FOREACH_SAFE(counter, counter_hash + i, nodes,
1330 tmp_counter) {
1331 key = counter->key;
1332 key_index = 1;
1333
1334 ipver = key[0];
1335
1336 memcpy(laddr, key + key_index, sizeof(laddr));
1337 key_index += sizeof(laddr);
1338 memcpy(&lport, key + key_index, sizeof(lport));
1339 key_index += sizeof(lport);
1340 memcpy(faddr, key + key_index, sizeof(faddr));
1341 key_index += sizeof(faddr);
1342 memcpy(&fport, key + key_index, sizeof(fport));
1343
1344 #ifdef SIFTR_IPV6
1345 laddr[3] = ntohl(laddr[3]);
1346 faddr[3] = ntohl(faddr[3]);
1347
1348 if (ipver == INP_IPV6) {
1349 laddr[0] = ntohl(laddr[0]);
1350 laddr[1] = ntohl(laddr[1]);
1351 laddr[2] = ntohl(laddr[2]);
1352 faddr[0] = ntohl(faddr[0]);
1353 faddr[1] = ntohl(faddr[1]);
1354 faddr[2] = ntohl(faddr[2]);
1355
1356 sbuf_printf(s,
1357 "%x:%x:%x:%x:%x:%x:%x:%x;%u-"
1358 "%x:%x:%x:%x:%x:%x:%x:%x;%u,",
1359 UPPER_SHORT(laddr[0]),
1360 LOWER_SHORT(laddr[0]),
1361 UPPER_SHORT(laddr[1]),
1362 LOWER_SHORT(laddr[1]),
1363 UPPER_SHORT(laddr[2]),
1364 LOWER_SHORT(laddr[2]),
1365 UPPER_SHORT(laddr[3]),
1366 LOWER_SHORT(laddr[3]),
1367 ntohs(lport),
1368 UPPER_SHORT(faddr[0]),
1369 LOWER_SHORT(faddr[0]),
1370 UPPER_SHORT(faddr[1]),
1371 LOWER_SHORT(faddr[1]),
1372 UPPER_SHORT(faddr[2]),
1373 LOWER_SHORT(faddr[2]),
1374 UPPER_SHORT(faddr[3]),
1375 LOWER_SHORT(faddr[3]),
1376 ntohs(fport));
1377 } else {
1378 laddr[0] = FIRST_OCTET(laddr[3]);
1379 laddr[1] = SECOND_OCTET(laddr[3]);
1380 laddr[2] = THIRD_OCTET(laddr[3]);
1381 laddr[3] = FOURTH_OCTET(laddr[3]);
1382 faddr[0] = FIRST_OCTET(faddr[3]);
1383 faddr[1] = SECOND_OCTET(faddr[3]);
1384 faddr[2] = THIRD_OCTET(faddr[3]);
1385 faddr[3] = FOURTH_OCTET(faddr[3]);
1386 #endif
1387 sbuf_printf(s,
1388 "%u.%u.%u.%u;%u-%u.%u.%u.%u;%u,",
1389 laddr[0],
1390 laddr[1],
1391 laddr[2],
1392 laddr[3],
1393 ntohs(lport),
1394 faddr[0],
1395 faddr[1],
1396 faddr[2],
1397 faddr[3],
1398 ntohs(fport));
1399 #ifdef SIFTR_IPV6
1400 }
1401 #endif
1402
1403 free(counter, M_SIFTR_HASHNODE);
1404 }
1405
1406 LIST_INIT(counter_hash + i);
1407 }
1408
1409 sbuf_printf(s, "\n");
1410 sbuf_finish(s);
1411
1412 i = 0;
1413 do {
1414 bytes_to_write = min(SIFTR_ALQ_BUFLEN, sbuf_len(s)-i);
1415 alq_writen(siftr_alq, sbuf_data(s)+i, bytes_to_write, ALQ_WAITOK);
1416 i += bytes_to_write;
1417 } while (i < sbuf_len(s));
1418
1419 alq_close(siftr_alq);
1420 siftr_alq = NULL;
1421 }
1422
1423 sbuf_delete(s);
1424
1425 /*
1426 * XXX: Should be using ret to check if any functions fail
1427 * and set error appropriately
1428 */
1429
1430 return (error);
1431 }
1432
1433
1434 static int
1435 siftr_sysctl_enabled_handler(SYSCTL_HANDLER_ARGS)
1436 {
1437 if (req->newptr == NULL)
1438 goto skip;
1439
1440 /* If the value passed in isn't 0 or 1, return an error. */
1441 if (CAST_PTR_INT(req->newptr) != 0 && CAST_PTR_INT(req->newptr) != 1)
1442 return (1);
1443
1444 /* If we are changing state (0 to 1 or 1 to 0). */
1445 if (CAST_PTR_INT(req->newptr) != siftr_enabled )
1446 if (siftr_manage_ops(CAST_PTR_INT(req->newptr))) {
1447 siftr_manage_ops(SIFTR_DISABLE);
1448 return (1);
1449 }
1450
1451 skip:
1452 return (sysctl_handle_int(oidp, arg1, arg2, req));
1453 }
1454
1455
1456 static void
1457 siftr_shutdown_handler(void *arg)
1458 {
1459 siftr_manage_ops(SIFTR_DISABLE);
1460 }
1461
1462
1463 /*
1464 * Module is being unloaded or machine is shutting down. Take care of cleanup.
1465 */
1466 static int
1467 deinit_siftr(void)
1468 {
1469 /* Cleanup. */
1470 siftr_manage_ops(SIFTR_DISABLE);
1471 hashdestroy(counter_hash, M_SIFTR, siftr_hashmask);
1472 mtx_destroy(&siftr_pkt_queue_mtx);
1473 mtx_destroy(&siftr_pkt_mgr_mtx);
1474
1475 return (0);
1476 }
1477
1478
1479 /*
1480 * Module has just been loaded into the kernel.
1481 */
1482 static int
1483 init_siftr(void)
1484 {
1485 EVENTHANDLER_REGISTER(shutdown_pre_sync, siftr_shutdown_handler, NULL,
1486 SHUTDOWN_PRI_FIRST);
1487
1488 /* Initialise our flow counter hash table. */
1489 counter_hash = hashinit(SIFTR_EXPECTED_MAX_TCP_FLOWS, M_SIFTR,
1490 &siftr_hashmask);
1491
1492 mtx_init(&siftr_pkt_queue_mtx, "siftr_pkt_queue_mtx", NULL, MTX_DEF);
1493 mtx_init(&siftr_pkt_mgr_mtx, "siftr_pkt_mgr_mtx", NULL, MTX_DEF);
1494
1495 /* Print message to the user's current terminal. */
1496 uprintf("\nStatistical Information For TCP Research (SIFTR) %s\n"
1497 " http://caia.swin.edu.au/urp/newtcp\n\n",
1498 MODVERSION_STR);
1499
1500 return (0);
1501 }
1502
1503
1504 /*
1505 * This is the function that is called to load and unload the module.
1506 * When the module is loaded, this function is called once with
1507 * "what" == MOD_LOAD
1508 * When the module is unloaded, this function is called twice with
1509 * "what" = MOD_QUIESCE first, followed by "what" = MOD_UNLOAD second
1510 * When the system is shut down e.g. CTRL-ALT-DEL or using the shutdown command,
1511 * this function is called once with "what" = MOD_SHUTDOWN
1512 * When the system is shut down, the handler isn't called until the very end
1513 * of the shutdown sequence i.e. after the disks have been synced.
1514 */
1515 static int
1516 siftr_load_handler(module_t mod, int what, void *arg)
1517 {
1518 int ret;
1519
1520 switch (what) {
1521 case MOD_LOAD:
1522 ret = init_siftr();
1523 break;
1524
1525 case MOD_QUIESCE:
1526 case MOD_SHUTDOWN:
1527 ret = deinit_siftr();
1528 break;
1529
1530 case MOD_UNLOAD:
1531 ret = 0;
1532 break;
1533
1534 default:
1535 ret = EINVAL;
1536 break;
1537 }
1538
1539 return (ret);
1540 }
1541
1542
1543 static moduledata_t siftr_mod = {
1544 .name = "siftr",
1545 .evhand = siftr_load_handler,
1546 };
1547
1548 /*
1549 * Param 1: name of the kernel module
1550 * Param 2: moduledata_t struct containing info about the kernel module
1551 * and the execution entry point for the module
1552 * Param 3: From sysinit_sub_id enumeration in /usr/include/sys/kernel.h
1553 * Defines the module initialisation order
1554 * Param 4: From sysinit_elem_order enumeration in /usr/include/sys/kernel.h
1555 * Defines the initialisation order of this kld relative to others
1556 * within the same subsystem as defined by param 3
1557 */
1558 DECLARE_MODULE(siftr, siftr_mod, SI_SUB_SMP, SI_ORDER_ANY);
1559 MODULE_DEPEND(siftr, alq, 1, 1, 1);
1560 MODULE_VERSION(siftr, MODVERSION);
Cache object: bf29cbd58d7dc05a41ad6cdc378a62e9
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