2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2016-2018 Netflix, Inc.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
32 #include <sys/param.h>
34 #include <sys/kernel.h>
36 #include <sys/malloc.h>
37 #include <sys/mutex.h>
38 #include <sys/qmath.h>
39 #include <sys/queue.h>
40 #include <sys/refcount.h>
41 #include <sys/rwlock.h>
42 #include <sys/socket.h>
43 #include <sys/socketvar.h>
44 #include <sys/sysctl.h>
46 #include <sys/stats.h>
47 #include <sys/counter.h>
49 #include <dev/tcp_log/tcp_log_dev.h>
52 #include <net/if_var.h>
55 #include <netinet/in.h>
56 #include <netinet/in_pcb.h>
57 #include <netinet/in_var.h>
58 #include <netinet/tcp_var.h>
59 #include <netinet/tcp_log_buf.h>
61 /* Default expiry time */
62 #define TCP_LOG_EXPIRE_TIME ((sbintime_t)60 * SBT_1S)
64 /* Max interval at which to run the expiry timer */
65 #define TCP_LOG_EXPIRE_INTVL ((sbintime_t)5 * SBT_1S)
68 static uma_zone_t tcp_log_bucket_zone, tcp_log_node_zone, tcp_log_zone;
69 static int tcp_log_session_limit = TCP_LOG_BUF_DEFAULT_SESSION_LIMIT;
70 static uint32_t tcp_log_version = TCP_LOG_BUF_VER;
71 RB_HEAD(tcp_log_id_tree, tcp_log_id_bucket);
72 static struct tcp_log_id_tree tcp_log_id_head;
73 static STAILQ_HEAD(, tcp_log_id_node) tcp_log_expireq_head =
74 STAILQ_HEAD_INITIALIZER(tcp_log_expireq_head);
75 static struct mtx tcp_log_expireq_mtx;
76 static struct callout tcp_log_expireq_callout;
77 static u_long tcp_log_auto_ratio = 0;
78 static volatile u_long tcp_log_auto_ratio_cur = 0;
79 static uint32_t tcp_log_auto_mode = TCP_LOG_STATE_TAIL;
80 static bool tcp_log_auto_all = false;
82 RB_PROTOTYPE_STATIC(tcp_log_id_tree, tcp_log_id_bucket, tlb_rb, tcp_log_id_cmp)
84 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, bb, CTLFLAG_RW, 0, "TCP Black Box controls");
86 SYSCTL_BOOL(_net_inet_tcp_bb, OID_AUTO, log_verbose, CTLFLAG_RW, &tcp_log_verbose,
87 0, "Force verbose logging for TCP traces");
89 SYSCTL_INT(_net_inet_tcp_bb, OID_AUTO, log_session_limit,
90 CTLFLAG_RW, &tcp_log_session_limit, 0,
91 "Maximum number of events maintained for each TCP session");
93 SYSCTL_UMA_MAX(_net_inet_tcp_bb, OID_AUTO, log_global_limit, CTLFLAG_RW,
94 &tcp_log_zone, "Maximum number of events maintained for all TCP sessions");
96 SYSCTL_UMA_CUR(_net_inet_tcp_bb, OID_AUTO, log_global_entries, CTLFLAG_RD,
97 &tcp_log_zone, "Current number of events maintained for all TCP sessions");
99 SYSCTL_UMA_MAX(_net_inet_tcp_bb, OID_AUTO, log_id_limit, CTLFLAG_RW,
100 &tcp_log_bucket_zone, "Maximum number of log IDs");
102 SYSCTL_UMA_CUR(_net_inet_tcp_bb, OID_AUTO, log_id_entries, CTLFLAG_RD,
103 &tcp_log_bucket_zone, "Current number of log IDs");
105 SYSCTL_UMA_MAX(_net_inet_tcp_bb, OID_AUTO, log_id_tcpcb_limit, CTLFLAG_RW,
106 &tcp_log_node_zone, "Maximum number of tcpcbs with log IDs");
108 SYSCTL_UMA_CUR(_net_inet_tcp_bb, OID_AUTO, log_id_tcpcb_entries, CTLFLAG_RD,
109 &tcp_log_node_zone, "Current number of tcpcbs with log IDs");
111 SYSCTL_U32(_net_inet_tcp_bb, OID_AUTO, log_version, CTLFLAG_RD, &tcp_log_version,
112 0, "Version of log formats exported");
114 SYSCTL_ULONG(_net_inet_tcp_bb, OID_AUTO, log_auto_ratio, CTLFLAG_RW,
115 &tcp_log_auto_ratio, 0, "Do auto capturing for 1 out of N sessions");
117 SYSCTL_U32(_net_inet_tcp_bb, OID_AUTO, log_auto_mode, CTLFLAG_RW,
118 &tcp_log_auto_mode, TCP_LOG_STATE_HEAD_AUTO,
119 "Logging mode for auto-selected sessions (default is TCP_LOG_STATE_HEAD_AUTO)");
121 SYSCTL_BOOL(_net_inet_tcp_bb, OID_AUTO, log_auto_all, CTLFLAG_RW,
122 &tcp_log_auto_all, false,
123 "Auto-select from all sessions (rather than just those with IDs)");
125 #ifdef TCPLOG_DEBUG_COUNTERS
126 counter_u64_t tcp_log_queued;
127 counter_u64_t tcp_log_que_fail1;
128 counter_u64_t tcp_log_que_fail2;
129 counter_u64_t tcp_log_que_fail3;
130 counter_u64_t tcp_log_que_fail4;
131 counter_u64_t tcp_log_que_fail5;
132 counter_u64_t tcp_log_que_copyout;
133 counter_u64_t tcp_log_que_read;
134 counter_u64_t tcp_log_que_freed;
136 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, queued, CTLFLAG_RD,
137 &tcp_log_queued, "Number of entries queued");
138 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, fail1, CTLFLAG_RD,
139 &tcp_log_que_fail1, "Number of entries queued but fail 1");
140 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, fail2, CTLFLAG_RD,
141 &tcp_log_que_fail2, "Number of entries queued but fail 2");
142 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, fail3, CTLFLAG_RD,
143 &tcp_log_que_fail3, "Number of entries queued but fail 3");
144 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, fail4, CTLFLAG_RD,
145 &tcp_log_que_fail4, "Number of entries queued but fail 4");
146 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, fail5, CTLFLAG_RD,
147 &tcp_log_que_fail5, "Number of entries queued but fail 4");
148 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, copyout, CTLFLAG_RD,
149 &tcp_log_que_copyout, "Number of entries copied out");
150 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, read, CTLFLAG_RD,
151 &tcp_log_que_read, "Number of entries read from the queue");
152 SYSCTL_COUNTER_U64(_net_inet_tcp_bb, OID_AUTO, freed, CTLFLAG_RD,
153 &tcp_log_que_freed, "Number of entries freed after reading");
157 #define TCPLOG_DEBUG_RINGBUF
162 STAILQ_ENTRY(tcp_log_mem) tlm_queue;
163 struct tcp_log_buffer tlm_buf;
164 struct tcp_log_verbose tlm_v;
165 #ifdef TCPLOG_DEBUG_RINGBUF
166 volatile int tlm_refcnt;
170 /* 60 bytes for the header, + 16 bytes for padding */
171 static uint8_t zerobuf[76];
180 * A. You need a lock on the Tree to add/remove buckets.
181 * B. You need a lock on the bucket to add/remove nodes from the bucket.
182 * C. To change information in a node, you need the INP lock if the tln_closed
183 * field is false. Otherwise, you need the bucket lock. (Note that the
184 * tln_closed field can change at any point, so you need to recheck the
185 * entry after acquiring the INP lock.)
186 * D. To remove a node from the bucket, you must have that entry locked,
187 * according to the criteria of Rule C. Also, the node must not be on
189 * E. The exception to C is the expiry queue fields, which are locked by
190 * the TCPLOG_EXPIREQ lock.
192 * Buckets have a reference count. Each node is a reference. Further,
193 * other callers may add reference counts to keep a bucket from disappearing.
194 * You can add a reference as long as you own a lock sufficient to keep the
195 * bucket from disappearing. For example, a common use is:
196 * a. Have a locked INP, but need to lock the TCPID_BUCKET.
197 * b. Add a refcount on the bucket. (Safe because the INP lock prevents
198 * the TCPID_BUCKET from going away.)
199 * c. Drop the INP lock.
200 * d. Acquire a lock on the TCPID_BUCKET.
201 * e. Acquire a lock on the INP.
202 * f. Drop the refcount on the bucket.
203 * (At this point, the bucket may disappear.)
206 * You can acquire this with either the bucket or INP lock. Don't reverse it.
207 * When the expire code has committed to freeing a node, it resets the expiry
208 * time to SBT_MAX. That is the signal to everyone else that they should
209 * leave that node alone.
211 static struct rwlock tcp_id_tree_lock;
212 #define TCPID_TREE_WLOCK() rw_wlock(&tcp_id_tree_lock)
213 #define TCPID_TREE_RLOCK() rw_rlock(&tcp_id_tree_lock)
214 #define TCPID_TREE_UPGRADE() rw_try_upgrade(&tcp_id_tree_lock)
215 #define TCPID_TREE_WUNLOCK() rw_wunlock(&tcp_id_tree_lock)
216 #define TCPID_TREE_RUNLOCK() rw_runlock(&tcp_id_tree_lock)
217 #define TCPID_TREE_WLOCK_ASSERT() rw_assert(&tcp_id_tree_lock, RA_WLOCKED)
218 #define TCPID_TREE_RLOCK_ASSERT() rw_assert(&tcp_id_tree_lock, RA_RLOCKED)
219 #define TCPID_TREE_UNLOCK_ASSERT() rw_assert(&tcp_id_tree_lock, RA_UNLOCKED)
221 #define TCPID_BUCKET_LOCK_INIT(tlb) mtx_init(&((tlb)->tlb_mtx), "tcp log id bucket", NULL, MTX_DEF)
222 #define TCPID_BUCKET_LOCK_DESTROY(tlb) mtx_destroy(&((tlb)->tlb_mtx))
223 #define TCPID_BUCKET_LOCK(tlb) mtx_lock(&((tlb)->tlb_mtx))
224 #define TCPID_BUCKET_UNLOCK(tlb) mtx_unlock(&((tlb)->tlb_mtx))
225 #define TCPID_BUCKET_LOCK_ASSERT(tlb) mtx_assert(&((tlb)->tlb_mtx), MA_OWNED)
226 #define TCPID_BUCKET_UNLOCK_ASSERT(tlb) mtx_assert(&((tlb)->tlb_mtx), MA_NOTOWNED)
228 #define TCPID_BUCKET_REF(tlb) refcount_acquire(&((tlb)->tlb_refcnt))
229 #define TCPID_BUCKET_UNREF(tlb) refcount_release(&((tlb)->tlb_refcnt))
231 #define TCPLOG_EXPIREQ_LOCK() mtx_lock(&tcp_log_expireq_mtx)
232 #define TCPLOG_EXPIREQ_UNLOCK() mtx_unlock(&tcp_log_expireq_mtx)
234 SLIST_HEAD(tcp_log_id_head, tcp_log_id_node);
236 struct tcp_log_id_bucket
239 * tlb_id must be first. This lets us use strcmp on
240 * (struct tcp_log_id_bucket *) and (char *) interchangeably.
242 char tlb_id[TCP_LOG_ID_LEN];
243 RB_ENTRY(tcp_log_id_bucket) tlb_rb;
244 struct tcp_log_id_head tlb_head;
246 volatile u_int tlb_refcnt;
249 struct tcp_log_id_node
251 SLIST_ENTRY(tcp_log_id_node) tln_list;
252 STAILQ_ENTRY(tcp_log_id_node) tln_expireq; /* Locked by the expireq lock */
253 sbintime_t tln_expiretime; /* Locked by the expireq lock */
256 * If INP is NULL, that means the connection has closed. We've
257 * saved the connection endpoint information and the log entries
258 * in the tln_ie and tln_entries members. We've also saved a pointer
259 * to the enclosing bucket here. If INP is not NULL, the information is
260 * in the PCB and not here.
262 struct inpcb *tln_inp;
263 struct tcpcb *tln_tp;
264 struct tcp_log_id_bucket *tln_bucket;
265 struct in_endpoints tln_ie;
266 struct tcp_log_stailq tln_entries;
268 volatile int tln_closed;
272 enum tree_lock_state {
278 /* Do we want to select this session for auto-logging? */
280 tcp_log_selectauto(void)
284 * If we are doing auto-capturing, figure out whether we will capture
287 if (tcp_log_auto_ratio &&
288 (atomic_fetchadd_long(&tcp_log_auto_ratio_cur, 1) %
289 tcp_log_auto_ratio) == 0)
295 tcp_log_id_cmp(struct tcp_log_id_bucket *a, struct tcp_log_id_bucket *b)
297 KASSERT(a != NULL, ("tcp_log_id_cmp: argument a is unexpectedly NULL"));
298 KASSERT(b != NULL, ("tcp_log_id_cmp: argument b is unexpectedly NULL"));
299 return strncmp(a->tlb_id, b->tlb_id, TCP_LOG_ID_LEN);
302 RB_GENERATE_STATIC(tcp_log_id_tree, tcp_log_id_bucket, tlb_rb, tcp_log_id_cmp)
305 tcp_log_id_validate_tree_lock(int tree_locked)
309 switch (tree_locked) {
311 TCPID_TREE_WLOCK_ASSERT();
314 TCPID_TREE_RLOCK_ASSERT();
317 TCPID_TREE_UNLOCK_ASSERT();
320 kassert_panic("%s:%d: unknown tree lock state", __func__,
327 tcp_log_remove_bucket(struct tcp_log_id_bucket *tlb)
330 TCPID_TREE_WLOCK_ASSERT();
331 KASSERT(SLIST_EMPTY(&tlb->tlb_head),
332 ("%s: Attempt to remove non-empty bucket", __func__));
333 if (RB_REMOVE(tcp_log_id_tree, &tcp_log_id_head, tlb) == NULL) {
335 kassert_panic("%s:%d: error removing element from tree",
339 TCPID_BUCKET_LOCK_DESTROY(tlb);
340 uma_zfree(tcp_log_bucket_zone, tlb);
344 * Call with a referenced and locked bucket.
345 * Will return true if the bucket was freed; otherwise, false.
346 * tlb: The bucket to unreference.
347 * tree_locked: A pointer to the state of the tree lock. If the tree lock
348 * state changes, the function will update it.
349 * inp: If not NULL and the function needs to drop the inp lock to relock the
350 * tree, it will do so. (The caller must ensure inp will not become invalid,
351 * probably by holding a reference to it.)
354 tcp_log_unref_bucket(struct tcp_log_id_bucket *tlb, int *tree_locked,
358 KASSERT(tlb != NULL, ("%s: called with NULL tlb", __func__));
359 KASSERT(tree_locked != NULL, ("%s: called with NULL tree_locked",
362 tcp_log_id_validate_tree_lock(*tree_locked);
365 * Did we hold the last reference on the tlb? If so, we may need
366 * to free it. (Note that we can realistically only execute the
367 * loop twice: once without a write lock and once with a write
370 while (TCPID_BUCKET_UNREF(tlb)) {
372 * We need a write lock on the tree to free this.
373 * If we can upgrade the tree lock, this is "easy". If we
374 * can't upgrade the tree lock, we need to do this the
375 * "hard" way: unwind all our locks and relock everything.
376 * In the meantime, anything could have changed. We even
377 * need to validate that we still need to free the bucket.
379 if (*tree_locked == TREE_RLOCKED && TCPID_TREE_UPGRADE())
380 *tree_locked = TREE_WLOCKED;
381 else if (*tree_locked != TREE_WLOCKED) {
382 TCPID_BUCKET_REF(tlb);
385 TCPID_BUCKET_UNLOCK(tlb);
386 if (*tree_locked == TREE_RLOCKED)
387 TCPID_TREE_RUNLOCK();
389 *tree_locked = TREE_WLOCKED;
390 TCPID_BUCKET_LOCK(tlb);
397 * We have an empty bucket and a write lock on the tree.
398 * Remove the empty bucket.
400 tcp_log_remove_bucket(tlb);
407 * Call with a locked bucket. This function will release the lock on the
408 * bucket before returning.
410 * The caller is responsible for freeing the tp->t_lin/tln node!
412 * Note: one of tp or both tlb and tln must be supplied.
414 * inp: A pointer to the inp. If the function needs to drop the inp lock to
415 * acquire the tree write lock, it will do so. (The caller must ensure inp
416 * will not become invalid, probably by holding a reference to it.)
417 * tp: A pointer to the tcpcb. (optional; if specified, tlb and tln are ignored)
418 * tlb: A pointer to the bucket. (optional; ignored if tp is specified)
419 * tln: A pointer to the node. (optional; ignored if tp is specified)
420 * tree_locked: A pointer to the state of the tree lock. If the tree lock
421 * state changes, the function will update it.
423 * Will return true if the INP lock was reacquired; otherwise, false.
426 tcp_log_remove_id_node(struct inpcb *inp, struct tcpcb *tp,
427 struct tcp_log_id_bucket *tlb, struct tcp_log_id_node *tln,
430 int orig_tree_locked;
432 KASSERT(tp != NULL || (tlb != NULL && tln != NULL),
433 ("%s: called with tp=%p, tlb=%p, tln=%p", __func__,
435 KASSERT(tree_locked != NULL, ("%s: called with NULL tree_locked",
441 KASSERT(tlb != NULL, ("%s: unexpectedly NULL tlb", __func__));
442 KASSERT(tln != NULL, ("%s: unexpectedly NULL tln", __func__));
445 tcp_log_id_validate_tree_lock(*tree_locked);
446 TCPID_BUCKET_LOCK_ASSERT(tlb);
449 * Remove the node, clear the log bucket and node from the TCPCB, and
450 * decrement the bucket refcount. In the process, if this is the
451 * last reference, the bucket will be freed.
453 SLIST_REMOVE(&tlb->tlb_head, tln, tcp_log_id_node, tln_list);
458 orig_tree_locked = *tree_locked;
459 if (!tcp_log_unref_bucket(tlb, tree_locked, inp))
460 TCPID_BUCKET_UNLOCK(tlb);
461 return (*tree_locked != orig_tree_locked);
464 #define RECHECK_INP_CLEAN(cleanup) do { \
465 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) { \
470 tp = intotcpcb(inp); \
473 #define RECHECK_INP() RECHECK_INP_CLEAN(/* noop */)
476 tcp_log_grow_tlb(char *tlb_id, struct tcpcb *tp)
479 INP_WLOCK_ASSERT(tp->t_inpcb);
482 if (V_tcp_perconn_stats_enable == 2 && tp->t_stats == NULL)
483 (void)tcp_stats_sample_rollthedice(tp, tlb_id, strlen(tlb_id));
488 * Set the TCP log ID for a TCPCB.
489 * Called with INPCB locked. Returns with it unlocked.
492 tcp_log_set_id(struct tcpcb *tp, char *id)
494 struct tcp_log_id_bucket *tlb, *tmp_tlb;
495 struct tcp_log_id_node *tln;
503 tree_locked = TREE_UNLOCKED;
504 bucket_locked = false;
507 INP_WLOCK_ASSERT(inp);
509 /* See if the ID is unchanged. */
510 if ((tp->t_lib != NULL && !strcmp(tp->t_lib->tlb_id, id)) ||
511 (tp->t_lib == NULL && *id == 0)) {
517 * If the TCPCB had a previous ID, we need to extricate it from
520 * Drop the TCPCB lock and lock the tree and the bucket.
521 * Because this is called in the socket context, we (theoretically)
522 * don't need to worry about the INPCB completely going away
525 if (tp->t_lib != NULL) {
527 TCPID_BUCKET_REF(tlb);
530 if (tree_locked == TREE_UNLOCKED) {
532 tree_locked = TREE_RLOCKED;
534 TCPID_BUCKET_LOCK(tlb);
535 bucket_locked = true;
539 * Unreference the bucket. If our bucket went away, it is no
540 * longer locked or valid.
542 if (tcp_log_unref_bucket(tlb, &tree_locked, inp)) {
543 bucket_locked = false;
547 /* Validate the INP. */
551 * Evaluate whether the bucket changed while we were unlocked.
553 * Possible scenarios here:
554 * 1. Bucket is unchanged and the same one we started with.
555 * 2. The TCPCB no longer has a bucket and our bucket was
557 * 3. The TCPCB has a new bucket, whether ours was freed.
558 * 4. The TCPCB no longer has a bucket and our bucket was
561 * In cases 2-4, we will start over. In case 1, we will
562 * proceed here to remove the bucket.
564 if (tlb == NULL || tp->t_lib != tlb) {
565 KASSERT(bucket_locked || tlb == NULL,
566 ("%s: bucket_locked (%d) and tlb (%p) are "
567 "inconsistent", __func__, bucket_locked, tlb));
570 TCPID_BUCKET_UNLOCK(tlb);
571 bucket_locked = false;
578 * Store the (struct tcp_log_id_node) for reuse. Then, remove
579 * it from the bucket. In the process, we may end up relocking.
580 * If so, we need to validate that the INP is still valid, and
581 * the TCPCB entries match we expect.
583 * We will clear tlb and change the bucket_locked state just
584 * before calling tcp_log_remove_id_node(), since that function
585 * will unlock the bucket.
588 uma_zfree(tcp_log_node_zone, tln);
591 bucket_locked = false;
592 if (tcp_log_remove_id_node(inp, tp, NULL, NULL, &tree_locked)) {
596 * If the TCPCB moved to a new bucket while we had
597 * dropped the lock, restart.
599 if (tp->t_lib != NULL || tp->t_lin != NULL)
604 * Yay! We successfully removed the TCPCB from its old
607 * On to bigger and better things...
611 /* At this point, the TCPCB should not be in any bucket. */
612 KASSERT(tp->t_lib == NULL, ("%s: tp->t_lib is not NULL", __func__));
615 * If the new ID is not empty, we need to now assign this TCPCB to a
619 /* Get a new tln, if we don't already have one to reuse. */
621 tln = uma_zalloc(tcp_log_node_zone, M_NOWAIT | M_ZERO);
631 * Drop the INP lock for a bit. We don't need it, and dropping
632 * it prevents lock order reversals.
636 /* Make sure we have at least a read lock on the tree. */
637 tcp_log_id_validate_tree_lock(tree_locked);
638 if (tree_locked == TREE_UNLOCKED) {
640 tree_locked = TREE_RLOCKED;
645 * Remember that we constructed (struct tcp_log_id_node) so
646 * we can safely cast the id to it for the purposes of finding.
648 KASSERT(tlb == NULL, ("%s:%d tlb unexpectedly non-NULL",
649 __func__, __LINE__));
650 tmp_tlb = RB_FIND(tcp_log_id_tree, &tcp_log_id_head,
651 (struct tcp_log_id_bucket *) id);
654 * If we didn't find a matching bucket, we need to add a new
655 * one. This requires a write lock. But, of course, we will
656 * need to recheck some things when we re-acquire the lock.
658 if (tmp_tlb == NULL && tree_locked != TREE_WLOCKED) {
659 tree_locked = TREE_WLOCKED;
660 if (!TCPID_TREE_UPGRADE()) {
661 TCPID_TREE_RUNLOCK();
665 * The tree may have changed while we were
672 /* If we need to add a new bucket, do it now. */
673 if (tmp_tlb == NULL) {
674 /* Allocate new bucket. */
675 tlb = uma_zalloc(tcp_log_bucket_zone, M_NOWAIT);
682 * Copy the ID to the bucket.
683 * NB: Don't use strlcpy() unless you are sure
684 * we've always validated NULL termination.
686 * TODO: When I'm done writing this, see if we
687 * we have correctly validated NULL termination and
688 * can use strlcpy(). :-)
690 strncpy(tlb->tlb_id, id, TCP_LOG_ID_LEN - 1);
691 tlb->tlb_id[TCP_LOG_ID_LEN - 1] = '\0';
694 * Take the refcount for the first node and go ahead
695 * and lock this. Note that we zero the tlb_mtx
696 * structure, since 0xdeadc0de flips the right bits
697 * for the code to think that this mutex has already
698 * been initialized. :-(
700 SLIST_INIT(&tlb->tlb_head);
701 refcount_init(&tlb->tlb_refcnt, 1);
702 memset(&tlb->tlb_mtx, 0, sizeof(struct mtx));
703 TCPID_BUCKET_LOCK_INIT(tlb);
704 TCPID_BUCKET_LOCK(tlb);
705 bucket_locked = true;
707 #define FREE_NEW_TLB() do { \
708 TCPID_BUCKET_LOCK_DESTROY(tlb); \
709 uma_zfree(tcp_log_bucket_zone, tlb); \
710 bucket_locked = false; \
714 * Relock the INP and make sure we are still
718 RECHECK_INP_CLEAN(FREE_NEW_TLB());
719 if (tp->t_lib != NULL) {
724 /* Add the new bucket to the tree. */
725 tmp_tlb = RB_INSERT(tcp_log_id_tree, &tcp_log_id_head,
727 KASSERT(tmp_tlb == NULL,
728 ("%s: Unexpected conflicting bucket (%p) while "
729 "adding new bucket (%p)", __func__, tmp_tlb, tlb));
732 * If we found a conflicting bucket, free the new
733 * one we made and fall through to use the existing
736 if (tmp_tlb != NULL) {
743 /* If we found an existing bucket, use it. */
744 if (tmp_tlb != NULL) {
746 TCPID_BUCKET_LOCK(tlb);
747 bucket_locked = true;
750 * Relock the INP and make sure we are still
753 INP_UNLOCK_ASSERT(inp);
756 if (tp->t_lib != NULL) {
757 TCPID_BUCKET_UNLOCK(tlb);
758 bucket_locked = false;
763 /* Take a reference on the bucket. */
764 TCPID_BUCKET_REF(tlb);
767 tcp_log_grow_tlb(tlb->tlb_id, tp);
769 /* Add the new node to the list. */
770 SLIST_INSERT_HEAD(&tlb->tlb_head, tln, tln_list);
779 /* Unlock things, as needed, and return. */
782 INP_UNLOCK_ASSERT(inp);
784 TCPID_BUCKET_LOCK_ASSERT(tlb);
785 TCPID_BUCKET_UNLOCK(tlb);
786 } else if (tlb != NULL)
787 TCPID_BUCKET_UNLOCK_ASSERT(tlb);
788 if (tree_locked == TREE_WLOCKED) {
789 TCPID_TREE_WLOCK_ASSERT();
790 TCPID_TREE_WUNLOCK();
791 } else if (tree_locked == TREE_RLOCKED) {
792 TCPID_TREE_RLOCK_ASSERT();
793 TCPID_TREE_RUNLOCK();
795 TCPID_TREE_UNLOCK_ASSERT();
797 uma_zfree(tcp_log_node_zone, tln);
802 * Get the TCP log ID for a TCPCB.
803 * Called with INPCB locked.
804 * 'buf' must point to a buffer that is at least TCP_LOG_ID_LEN bytes long.
805 * Returns number of bytes copied.
808 tcp_log_get_id(struct tcpcb *tp, char *buf)
812 INP_LOCK_ASSERT(tp->t_inpcb);
813 if (tp->t_lib != NULL) {
814 len = strlcpy(buf, tp->t_lib->tlb_id, TCP_LOG_ID_LEN);
815 KASSERT(len < TCP_LOG_ID_LEN,
816 ("%s:%d: tp->t_lib->tlb_id too long (%zu)",
817 __func__, __LINE__, len));
826 * Get number of connections with the same log ID.
827 * Log ID is taken from given TCPCB.
828 * Called with INPCB locked.
831 tcp_log_get_id_cnt(struct tcpcb *tp)
834 INP_WLOCK_ASSERT(tp->t_inpcb);
835 return ((tp->t_lib == NULL) ? 0 : tp->t_lib->tlb_refcnt);
838 #ifdef TCPLOG_DEBUG_RINGBUF
840 * Functions/macros to increment/decrement reference count for a log
841 * entry. This should catch when we do a double-free/double-remove or
845 _tcp_log_entry_refcnt_add(struct tcp_log_mem *log_entry, const char *func,
850 refcnt = atomic_fetchadd_int(&log_entry->tlm_refcnt, 1);
852 panic("%s:%d: log_entry(%p)->tlm_refcnt is %d (expected 0)",
853 func, line, log_entry, refcnt);
855 #define tcp_log_entry_refcnt_add(l) \
856 _tcp_log_entry_refcnt_add((l), __func__, __LINE__)
859 _tcp_log_entry_refcnt_rem(struct tcp_log_mem *log_entry, const char *func,
864 refcnt = atomic_fetchadd_int(&log_entry->tlm_refcnt, -1);
866 panic("%s:%d: log_entry(%p)->tlm_refcnt is %d (expected 1)",
867 func, line, log_entry, refcnt);
869 #define tcp_log_entry_refcnt_rem(l) \
870 _tcp_log_entry_refcnt_rem((l), __func__, __LINE__)
872 #else /* !TCPLOG_DEBUG_RINGBUF */
874 #define tcp_log_entry_refcnt_add(l)
875 #define tcp_log_entry_refcnt_rem(l)
880 * Cleanup after removing a log entry, but only decrement the count if we
881 * are running INVARIANTS.
884 tcp_log_free_log_common(struct tcp_log_mem *log_entry, int *count __unused)
887 uma_zfree(tcp_log_zone, log_entry);
891 ("%s: count unexpectedly negative", __func__));
896 tcp_log_free_entries(struct tcp_log_stailq *head, int *count)
898 struct tcp_log_mem *log_entry;
900 /* Free the entries. */
901 while ((log_entry = STAILQ_FIRST(head)) != NULL) {
902 STAILQ_REMOVE_HEAD(head, tlm_queue);
903 tcp_log_entry_refcnt_rem(log_entry);
904 tcp_log_free_log_common(log_entry, count);
908 /* Cleanup after removing a log entry. */
910 tcp_log_remove_log_cleanup(struct tcpcb *tp, struct tcp_log_mem *log_entry)
912 uma_zfree(tcp_log_zone, log_entry);
914 KASSERT(tp->t_lognum >= 0,
915 ("%s: tp->t_lognum unexpectedly negative", __func__));
918 /* Remove a log entry from the head of a list. */
920 tcp_log_remove_log_head(struct tcpcb *tp, struct tcp_log_mem *log_entry)
923 KASSERT(log_entry == STAILQ_FIRST(&tp->t_logs),
924 ("%s: attempt to remove non-HEAD log entry", __func__));
925 STAILQ_REMOVE_HEAD(&tp->t_logs, tlm_queue);
926 tcp_log_entry_refcnt_rem(log_entry);
927 tcp_log_remove_log_cleanup(tp, log_entry);
930 #ifdef TCPLOG_DEBUG_RINGBUF
932 * Initialize the log entry's reference count, which we want to
933 * survive allocations.
936 tcp_log_zone_init(void *mem, int size, int flags __unused)
938 struct tcp_log_mem *tlm;
940 KASSERT(size >= sizeof(struct tcp_log_mem),
941 ("%s: unexpectedly short (%d) allocation", __func__, size));
942 tlm = (struct tcp_log_mem *)mem;
948 * Double check that the refcnt is zero on allocation and return.
951 tcp_log_zone_ctor(void *mem, int size, void *args __unused, int flags __unused)
953 struct tcp_log_mem *tlm;
955 KASSERT(size >= sizeof(struct tcp_log_mem),
956 ("%s: unexpectedly short (%d) allocation", __func__, size));
957 tlm = (struct tcp_log_mem *)mem;
958 if (tlm->tlm_refcnt != 0)
959 panic("%s:%d: tlm(%p)->tlm_refcnt is %d (expected 0)",
960 __func__, __LINE__, tlm, tlm->tlm_refcnt);
965 tcp_log_zone_dtor(void *mem, int size, void *args __unused)
967 struct tcp_log_mem *tlm;
969 KASSERT(size >= sizeof(struct tcp_log_mem),
970 ("%s: unexpectedly short (%d) allocation", __func__, size));
971 tlm = (struct tcp_log_mem *)mem;
972 if (tlm->tlm_refcnt != 0)
973 panic("%s:%d: tlm(%p)->tlm_refcnt is %d (expected 0)",
974 __func__, __LINE__, tlm, tlm->tlm_refcnt);
976 #endif /* TCPLOG_DEBUG_RINGBUF */
978 /* Do global initialization. */
983 tcp_log_zone = uma_zcreate("tcp_log", sizeof(struct tcp_log_mem),
984 #ifdef TCPLOG_DEBUG_RINGBUF
985 tcp_log_zone_ctor, tcp_log_zone_dtor, tcp_log_zone_init,
989 NULL, UMA_ALIGN_PTR, 0);
990 (void)uma_zone_set_max(tcp_log_zone, TCP_LOG_BUF_DEFAULT_GLOBAL_LIMIT);
991 tcp_log_bucket_zone = uma_zcreate("tcp_log_bucket",
992 sizeof(struct tcp_log_id_bucket), NULL, NULL, NULL, NULL,
994 tcp_log_node_zone = uma_zcreate("tcp_log_node",
995 sizeof(struct tcp_log_id_node), NULL, NULL, NULL, NULL,
997 #ifdef TCPLOG_DEBUG_COUNTERS
998 tcp_log_queued = counter_u64_alloc(M_WAITOK);
999 tcp_log_que_fail1 = counter_u64_alloc(M_WAITOK);
1000 tcp_log_que_fail2 = counter_u64_alloc(M_WAITOK);
1001 tcp_log_que_fail3 = counter_u64_alloc(M_WAITOK);
1002 tcp_log_que_fail4 = counter_u64_alloc(M_WAITOK);
1003 tcp_log_que_fail5 = counter_u64_alloc(M_WAITOK);
1004 tcp_log_que_copyout = counter_u64_alloc(M_WAITOK);
1005 tcp_log_que_read = counter_u64_alloc(M_WAITOK);
1006 tcp_log_que_freed = counter_u64_alloc(M_WAITOK);
1009 rw_init_flags(&tcp_id_tree_lock, "TCP ID tree", RW_NEW);
1010 mtx_init(&tcp_log_expireq_mtx, "TCP log expireq", NULL, MTX_DEF);
1011 callout_init(&tcp_log_expireq_callout, 1);
1014 /* Do per-TCPCB initialization. */
1016 tcp_log_tcpcbinit(struct tcpcb *tp)
1019 /* A new TCPCB should start out zero-initialized. */
1020 STAILQ_INIT(&tp->t_logs);
1023 * If we are doing auto-capturing, figure out whether we will capture
1026 if (tcp_log_selectauto()) {
1027 tp->t_logstate = tcp_log_auto_mode;
1028 tp->t_flags2 |= TF2_LOG_AUTO;
1033 /* Remove entries */
1035 tcp_log_expire(void *unused __unused)
1037 struct tcp_log_id_bucket *tlb;
1038 struct tcp_log_id_node *tln;
1039 sbintime_t expiry_limit;
1042 TCPLOG_EXPIREQ_LOCK();
1043 if (callout_pending(&tcp_log_expireq_callout)) {
1044 /* Callout was reset. */
1045 TCPLOG_EXPIREQ_UNLOCK();
1050 * Process entries until we reach one that expires too far in the
1051 * future. Look one second in the future.
1053 expiry_limit = getsbinuptime() + SBT_1S;
1054 tree_locked = TREE_UNLOCKED;
1056 while ((tln = STAILQ_FIRST(&tcp_log_expireq_head)) != NULL &&
1057 tln->tln_expiretime <= expiry_limit) {
1058 if (!callout_active(&tcp_log_expireq_callout)) {
1060 * Callout was stopped. I guess we should
1061 * just quit at this point.
1063 TCPLOG_EXPIREQ_UNLOCK();
1068 * Remove the node from the head of the list and unlock
1069 * the list. Change the expiry time to SBT_MAX as a signal
1070 * to other threads that we now own this.
1072 STAILQ_REMOVE_HEAD(&tcp_log_expireq_head, tln_expireq);
1073 tln->tln_expiretime = SBT_MAX;
1074 TCPLOG_EXPIREQ_UNLOCK();
1077 * Remove the node from the bucket.
1079 tlb = tln->tln_bucket;
1080 TCPID_BUCKET_LOCK(tlb);
1081 if (tcp_log_remove_id_node(NULL, NULL, tlb, tln, &tree_locked)) {
1082 tcp_log_id_validate_tree_lock(tree_locked);
1083 if (tree_locked == TREE_WLOCKED)
1084 TCPID_TREE_WUNLOCK();
1086 TCPID_TREE_RUNLOCK();
1087 tree_locked = TREE_UNLOCKED;
1090 /* Drop the INP reference. */
1091 INP_WLOCK(tln->tln_inp);
1092 if (!in_pcbrele_wlocked(tln->tln_inp))
1093 INP_WUNLOCK(tln->tln_inp);
1095 /* Free the log records. */
1096 tcp_log_free_entries(&tln->tln_entries, &tln->tln_count);
1098 /* Free the node. */
1099 uma_zfree(tcp_log_node_zone, tln);
1101 /* Relock the expiry queue. */
1102 TCPLOG_EXPIREQ_LOCK();
1106 * We've expired all the entries we can. Do we need to reschedule
1109 callout_deactivate(&tcp_log_expireq_callout);
1112 * Get max(now + TCP_LOG_EXPIRE_INTVL, tln->tln_expiretime) and
1113 * set the next callout to that. (This helps ensure we generally
1114 * run the callout no more often than desired.)
1116 expiry_limit = getsbinuptime() + TCP_LOG_EXPIRE_INTVL;
1117 if (expiry_limit < tln->tln_expiretime)
1118 expiry_limit = tln->tln_expiretime;
1119 callout_reset_sbt(&tcp_log_expireq_callout, expiry_limit,
1120 SBT_1S, tcp_log_expire, NULL, C_ABSOLUTE);
1124 TCPLOG_EXPIREQ_UNLOCK();
1129 * Move log data from the TCPCB to a new node. This will reset the TCPCB log
1130 * entries and log count; however, it will not touch other things from the
1131 * TCPCB (e.g. t_lin, t_lib).
1133 * NOTE: Must hold a lock on the INP.
1136 tcp_log_move_tp_to_node(struct tcpcb *tp, struct tcp_log_id_node *tln)
1139 INP_WLOCK_ASSERT(tp->t_inpcb);
1141 tln->tln_ie = tp->t_inpcb->inp_inc.inc_ie;
1142 if (tp->t_inpcb->inp_inc.inc_flags & INC_ISIPV6)
1143 tln->tln_af = AF_INET6;
1145 tln->tln_af = AF_INET;
1146 tln->tln_entries = tp->t_logs;
1147 tln->tln_count = tp->t_lognum;
1148 tln->tln_bucket = tp->t_lib;
1150 /* Clear information from the PCB. */
1151 STAILQ_INIT(&tp->t_logs);
1155 /* Do per-TCPCB cleanup */
1157 tcp_log_tcpcbfini(struct tcpcb *tp)
1159 struct tcp_log_id_node *tln, *tln_first;
1160 struct tcp_log_mem *log_entry;
1161 sbintime_t callouttime;
1163 INP_WLOCK_ASSERT(tp->t_inpcb);
1166 * If we were gathering packets to be automatically dumped, try to do
1167 * it now. If this succeeds, the log information in the TCPCB will be
1168 * cleared. Otherwise, we'll handle the log information as we do
1171 switch(tp->t_logstate) {
1172 case TCP_LOG_STATE_HEAD_AUTO:
1173 (void)tcp_log_dump_tp_logbuf(tp, "auto-dumped from head",
1176 case TCP_LOG_STATE_TAIL_AUTO:
1177 (void)tcp_log_dump_tp_logbuf(tp, "auto-dumped from tail",
1180 case TCP_LOG_STATE_CONTINUAL:
1181 (void)tcp_log_dump_tp_logbuf(tp, "auto-dumped from continual",
1187 * There are two ways we could keep logs: per-socket or per-ID. If
1188 * we are tracking logs with an ID, then the logs survive the
1189 * destruction of the TCPCB.
1191 * If the TCPCB is associated with an ID node, move the logs from the
1192 * TCPCB to the ID node. In theory, this is safe, for reasons which I
1193 * will now explain for my own benefit when I next need to figure out
1196 * We own the INP lock. Therefore, no one else can change the contents
1197 * of this node (Rule C). Further, no one can remove this node from
1198 * the bucket while we hold the lock (Rule D). Basically, no one can
1199 * mess with this node. That leaves two states in which we could be:
1201 * 1. Another thread is currently waiting to acquire the INP lock, with
1202 * plans to do something with this node. When we drop the INP lock,
1203 * they will have a chance to do that. They will recheck the
1204 * tln_closed field (see note to Rule C) and then acquire the
1205 * bucket lock before proceeding further.
1207 * 2. Another thread will try to acquire a lock at some point in the
1208 * future. If they try to acquire a lock before we set the
1209 * tln_closed field, they will follow state #1. If they try to
1210 * acquire a lock after we set the tln_closed field, they will be
1211 * able to make changes to the node, at will, following Rule C.
1213 * Therefore, we currently own this node and can make any changes
1214 * we want. But, as soon as we set the tln_closed field to true, we
1215 * have effectively dropped our lock on the node. (For this reason, we
1216 * also need to make sure our writes are ordered correctly. An atomic
1217 * operation with "release" semantics should be sufficient.)
1220 if (tp->t_lin != NULL) {
1221 /* Copy the relevant information to the log entry. */
1223 KASSERT(tln->tln_inp == tp->t_inpcb,
1224 ("%s: Mismatched inp (tln->tln_inp=%p, tp->t_inpcb=%p)",
1225 __func__, tln->tln_inp, tp->t_inpcb));
1226 tcp_log_move_tp_to_node(tp, tln);
1228 /* Clear information from the PCB. */
1233 * Take a reference on the INP. This ensures that the INP
1234 * remains valid while the node is on the expiry queue. This
1235 * ensures the INP is valid for other threads that may be
1236 * racing to lock this node when we move it to the expire
1239 in_pcbref(tp->t_inpcb);
1242 * Store the entry on the expiry list. The exact behavior
1243 * depends on whether we have entries to keep. If so, we
1244 * put the entry at the tail of the list and expire in
1245 * TCP_LOG_EXPIRE_TIME. Otherwise, we expire "now" and put
1246 * the entry at the head of the list. (Handling the cleanup
1247 * via the expiry timer lets us avoid locking messy-ness here.)
1249 tln->tln_expiretime = getsbinuptime();
1250 TCPLOG_EXPIREQ_LOCK();
1251 if (tln->tln_count) {
1252 tln->tln_expiretime += TCP_LOG_EXPIRE_TIME;
1253 if (STAILQ_EMPTY(&tcp_log_expireq_head) &&
1254 !callout_active(&tcp_log_expireq_callout)) {
1256 * We are adding the first entry and a callout
1257 * is not currently scheduled; therefore, we
1258 * need to schedule one.
1260 callout_reset_sbt(&tcp_log_expireq_callout,
1261 tln->tln_expiretime, SBT_1S, tcp_log_expire,
1264 STAILQ_INSERT_TAIL(&tcp_log_expireq_head, tln,
1267 callouttime = tln->tln_expiretime +
1268 TCP_LOG_EXPIRE_INTVL;
1269 tln_first = STAILQ_FIRST(&tcp_log_expireq_head);
1271 if ((tln_first == NULL ||
1272 callouttime < tln_first->tln_expiretime) &&
1273 (callout_pending(&tcp_log_expireq_callout) ||
1274 !callout_active(&tcp_log_expireq_callout))) {
1276 * The list is empty, or we want to run the
1277 * expire code before the first entry's timer
1278 * fires. Also, we are in a case where a callout
1279 * is not actively running. We want to reset
1280 * the callout to occur sooner.
1282 callout_reset_sbt(&tcp_log_expireq_callout,
1283 callouttime, SBT_1S, tcp_log_expire, NULL,
1288 * Insert to the head, or just after the head, as
1289 * appropriate. (This might result in small
1290 * mis-orderings as a bunch of "expire now" entries
1291 * gather at the start of the list, but that should
1292 * not produce big problems, since the expire timer
1293 * will walk through all of them.)
1295 if (tln_first == NULL ||
1296 tln->tln_expiretime < tln_first->tln_expiretime)
1297 STAILQ_INSERT_HEAD(&tcp_log_expireq_head, tln,
1300 STAILQ_INSERT_AFTER(&tcp_log_expireq_head,
1301 tln_first, tln, tln_expireq);
1303 TCPLOG_EXPIREQ_UNLOCK();
1306 * We are done messing with the tln. After this point, we
1307 * can't touch it. (Note that the "release" semantics should
1308 * be included with the TCPLOG_EXPIREQ_UNLOCK() call above.
1309 * Therefore, they should be unnecessary here. However, it
1310 * seems like a good idea to include them anyway, since we
1311 * really are releasing a lock here.)
1313 atomic_store_rel_int(&tln->tln_closed, 1);
1315 /* Remove log entries. */
1316 while ((log_entry = STAILQ_FIRST(&tp->t_logs)) != NULL)
1317 tcp_log_remove_log_head(tp, log_entry);
1318 KASSERT(tp->t_lognum == 0,
1319 ("%s: After freeing entries, tp->t_lognum=%d (expected 0)",
1320 __func__, tp->t_lognum));
1324 * Change the log state to off (just in case anything tries to sneak
1325 * in a last-minute log).
1327 tp->t_logstate = TCP_LOG_STATE_OFF;
1331 * This logs an event for a TCP socket. Normally, this is called via
1332 * TCP_LOG_EVENT or TCP_LOG_EVENT_VERBOSE. See the documentation for
1336 struct tcp_log_buffer *
1337 tcp_log_event_(struct tcpcb *tp, struct tcphdr *th, struct sockbuf *rxbuf,
1338 struct sockbuf *txbuf, uint8_t eventid, int errornum, uint32_t len,
1339 union tcp_log_stackspecific *stackinfo, int th_hostorder,
1340 const char *output_caller, const char *func, int line, const struct timeval *itv)
1342 struct tcp_log_mem *log_entry;
1343 struct tcp_log_buffer *log_buf;
1344 int attempt_count = 0;
1345 struct tcp_log_verbose *log_verbose;
1348 KASSERT((func == NULL && line == 0) || (func != NULL && line > 0),
1349 ("%s called with inconsistent func (%p) and line (%d) arguments",
1350 __func__, func, line));
1352 INP_WLOCK_ASSERT(tp->t_inpcb);
1354 KASSERT(tp->t_logstate == TCP_LOG_STATE_HEAD ||
1355 tp->t_logstate == TCP_LOG_STATE_TAIL ||
1356 tp->t_logstate == TCP_LOG_STATE_CONTINUAL ||
1357 tp->t_logstate == TCP_LOG_STATE_HEAD_AUTO ||
1358 tp->t_logstate == TCP_LOG_STATE_TAIL_AUTO,
1359 ("%s called with unexpected tp->t_logstate (%d)", __func__,
1363 * Get the serial number. We do this early so it will
1364 * increment even if we end up skipping the log entry for some
1367 logsn = tp->t_logsn++;
1370 * Can we get a new log entry? If so, increment the lognum counter
1374 if (tp->t_lognum < tcp_log_session_limit) {
1375 if ((log_entry = uma_zalloc(tcp_log_zone, M_NOWAIT)) != NULL)
1380 /* Do we need to try to reuse? */
1381 if (log_entry == NULL) {
1383 * Sacrifice auto-logged sessions without a log ID if
1384 * tcp_log_auto_all is false. (If they don't have a log
1385 * ID by now, it is probable that either they won't get one
1386 * or we are resource-constrained.)
1388 if (tp->t_lib == NULL && (tp->t_flags2 & TF2_LOG_AUTO) &&
1389 !tcp_log_auto_all) {
1390 if (tcp_log_state_change(tp, TCP_LOG_STATE_CLEAR)) {
1392 panic("%s:%d: tcp_log_state_change() failed "
1393 "to set tp %p to TCP_LOG_STATE_CLEAR",
1394 __func__, __LINE__, tp);
1396 tp->t_logstate = TCP_LOG_STATE_OFF;
1401 * If we are in TCP_LOG_STATE_HEAD_AUTO state, try to dump
1402 * the buffers. If successful, deactivate tracing. Otherwise,
1403 * leave it active so we will retry.
1405 if (tp->t_logstate == TCP_LOG_STATE_HEAD_AUTO &&
1406 !tcp_log_dump_tp_logbuf(tp, "auto-dumped from head",
1408 tp->t_logstate = TCP_LOG_STATE_OFF;
1410 } else if ((tp->t_logstate == TCP_LOG_STATE_CONTINUAL) &&
1411 !tcp_log_dump_tp_logbuf(tp, "auto-dumped from continual",
1413 if (attempt_count == 0) {
1417 #ifdef TCPLOG_DEBUG_COUNTERS
1418 counter_u64_add(tcp_log_que_fail4, 1);
1421 } else if (tp->t_logstate == TCP_LOG_STATE_HEAD_AUTO)
1424 /* If in HEAD state, just deactivate the tracing and return. */
1425 if (tp->t_logstate == TCP_LOG_STATE_HEAD) {
1426 tp->t_logstate = TCP_LOG_STATE_OFF;
1431 * Get a buffer to reuse. If that fails, just give up.
1432 * (We can't log anything without a buffer in which to
1435 * Note that we don't change the t_lognum counter
1436 * here. Because we are re-using the buffer, the total
1437 * number won't change.
1439 if ((log_entry = STAILQ_FIRST(&tp->t_logs)) == NULL)
1441 STAILQ_REMOVE_HEAD(&tp->t_logs, tlm_queue);
1442 tcp_log_entry_refcnt_rem(log_entry);
1445 KASSERT(log_entry != NULL,
1446 ("%s: log_entry unexpectedly NULL", __func__));
1448 /* Extract the log buffer and verbose buffer pointers. */
1449 log_buf = &log_entry->tlm_buf;
1450 log_verbose = &log_entry->tlm_v;
1452 /* Basic entries. */
1454 getmicrouptime(&log_buf->tlb_tv);
1456 memcpy(&log_buf->tlb_tv, itv, sizeof(struct timeval));
1457 log_buf->tlb_ticks = ticks;
1458 log_buf->tlb_sn = logsn;
1459 log_buf->tlb_stackid = tp->t_fb->tfb_id;
1460 log_buf->tlb_eventid = eventid;
1461 log_buf->tlb_eventflags = 0;
1462 log_buf->tlb_errno = errornum;
1464 /* Socket buffers */
1465 if (rxbuf != NULL) {
1466 log_buf->tlb_eventflags |= TLB_FLAG_RXBUF;
1467 log_buf->tlb_rxbuf.tls_sb_acc = rxbuf->sb_acc;
1468 log_buf->tlb_rxbuf.tls_sb_ccc = rxbuf->sb_ccc;
1469 log_buf->tlb_rxbuf.tls_sb_spare = 0;
1471 if (txbuf != NULL) {
1472 log_buf->tlb_eventflags |= TLB_FLAG_TXBUF;
1473 log_buf->tlb_txbuf.tls_sb_acc = txbuf->sb_acc;
1474 log_buf->tlb_txbuf.tls_sb_ccc = txbuf->sb_ccc;
1475 log_buf->tlb_txbuf.tls_sb_spare = 0;
1477 /* Copy values from tp to the log entry. */
1478 #define COPY_STAT(f) log_buf->tlb_ ## f = tp->f
1479 #define COPY_STAT_T(f) log_buf->tlb_ ## f = tp->t_ ## f
1481 COPY_STAT_T(starttime);
1486 COPY_STAT(snd_cwnd);
1488 COPY_STAT(snd_recover);
1490 COPY_STAT(snd_ssthresh);
1492 COPY_STAT_T(rttvar);
1496 COPY_STAT(sack_newdata);
1498 COPY_STAT_T(dupacks);
1499 COPY_STAT_T(segqlen);
1500 COPY_STAT(snd_numholes);
1501 COPY_STAT(snd_scale);
1502 COPY_STAT(rcv_scale);
1505 log_buf->tlb_flex1 = 0;
1506 log_buf->tlb_flex2 = 0;
1507 /* Copy stack-specific info. */
1508 if (stackinfo != NULL) {
1509 memcpy(&log_buf->tlb_stackinfo, stackinfo,
1510 sizeof(log_buf->tlb_stackinfo));
1511 log_buf->tlb_eventflags |= TLB_FLAG_STACKINFO;
1515 log_buf->tlb_len = len;
1519 log_buf->tlb_eventflags |= TLB_FLAG_HDR;
1520 log_buf->tlb_th = *th;
1522 tcp_fields_to_net(&log_buf->tlb_th);
1523 optlen = (th->th_off << 2) - sizeof (struct tcphdr);
1525 memcpy(log_buf->tlb_opts, th + 1, optlen);
1528 /* Verbose information */
1530 log_buf->tlb_eventflags |= TLB_FLAG_VERBOSE;
1531 if (output_caller != NULL)
1532 strlcpy(log_verbose->tlv_snd_frm, output_caller,
1535 *log_verbose->tlv_snd_frm = 0;
1536 strlcpy(log_verbose->tlv_trace_func, func, TCP_FUNC_LEN);
1537 log_verbose->tlv_trace_line = line;
1540 /* Insert the new log at the tail. */
1541 STAILQ_INSERT_TAIL(&tp->t_logs, log_entry, tlm_queue);
1542 tcp_log_entry_refcnt_add(log_entry);
1547 * Change the logging state for a TCPCB. Returns 0 on success or an
1548 * error code on failure.
1551 tcp_log_state_change(struct tcpcb *tp, int state)
1553 struct tcp_log_mem *log_entry;
1555 INP_WLOCK_ASSERT(tp->t_inpcb);
1557 case TCP_LOG_STATE_CLEAR:
1558 while ((log_entry = STAILQ_FIRST(&tp->t_logs)) != NULL)
1559 tcp_log_remove_log_head(tp, log_entry);
1562 case TCP_LOG_STATE_OFF:
1563 tp->t_logstate = TCP_LOG_STATE_OFF;
1566 case TCP_LOG_STATE_TAIL:
1567 case TCP_LOG_STATE_HEAD:
1568 case TCP_LOG_STATE_CONTINUAL:
1569 case TCP_LOG_STATE_HEAD_AUTO:
1570 case TCP_LOG_STATE_TAIL_AUTO:
1571 tp->t_logstate = state;
1578 tp->t_flags2 &= ~(TF2_LOG_AUTO);
1583 /* If tcp_drain() is called, flush half the log entries. */
1585 tcp_log_drain(struct tcpcb *tp)
1587 struct tcp_log_mem *log_entry, *next;
1590 INP_WLOCK_ASSERT(tp->t_inpcb);
1591 if ((target = tp->t_lognum / 2) == 0)
1595 * If we are logging the "head" packets, we want to discard
1596 * from the tail of the queue. Otherwise, we want to discard
1599 if (tp->t_logstate == TCP_LOG_STATE_HEAD ||
1600 tp->t_logstate == TCP_LOG_STATE_HEAD_AUTO) {
1601 skip = tp->t_lognum - target;
1602 STAILQ_FOREACH(log_entry, &tp->t_logs, tlm_queue)
1605 KASSERT(log_entry != NULL,
1606 ("%s: skipped through all entries!", __func__));
1607 if (log_entry == NULL)
1609 while ((next = STAILQ_NEXT(log_entry, tlm_queue)) != NULL) {
1610 STAILQ_REMOVE_AFTER(&tp->t_logs, log_entry, tlm_queue);
1611 tcp_log_entry_refcnt_rem(next);
1612 tcp_log_remove_log_cleanup(tp, next);
1617 KASSERT(target == 0,
1618 ("%s: After removing from tail, target was %d", __func__,
1620 } else if (tp->t_logstate == TCP_LOG_STATE_CONTINUAL) {
1621 (void)tcp_log_dump_tp_logbuf(tp, "auto-dumped from continual",
1624 while ((log_entry = STAILQ_FIRST(&tp->t_logs)) != NULL &&
1626 tcp_log_remove_log_head(tp, log_entry);
1627 KASSERT(target <= 0,
1628 ("%s: After removing from head, target was %d", __func__,
1630 KASSERT(tp->t_lognum > 0,
1631 ("%s: After removing from head, tp->t_lognum was %d",
1633 KASSERT(log_entry != NULL,
1634 ("%s: After removing from head, the tailq was empty",
1640 tcp_log_copyout(struct sockopt *sopt, void *src, void *dst, size_t len)
1643 if (sopt->sopt_td != NULL)
1644 return (copyout(src, dst, len));
1645 bcopy(src, dst, len);
1650 tcp_log_logs_to_buf(struct sockopt *sopt, struct tcp_log_stailq *log_tailqp,
1651 struct tcp_log_buffer **end, int count)
1653 struct tcp_log_buffer *out_entry;
1654 struct tcp_log_mem *log_entry;
1658 int orig_count = count;
1661 /* Copy the data out. */
1663 out_entry = (struct tcp_log_buffer *) sopt->sopt_val;
1664 STAILQ_FOREACH(log_entry, log_tailqp, tlm_queue) {
1667 ("%s:%d: Exceeded expected count (%d) processing list %p",
1668 __func__, __LINE__, orig_count, log_tailqp));
1670 #ifdef TCPLOG_DEBUG_COUNTERS
1671 counter_u64_add(tcp_log_que_copyout, 1);
1675 * Skip copying out the header if it isn't present.
1676 * Instead, copy out zeros (to ensure we don't leak info).
1677 * TODO: Make sure we truly do zero everything we don't
1680 if (log_entry->tlm_buf.tlb_eventflags & TLB_FLAG_HDR)
1681 entrysize = sizeof(struct tcp_log_buffer);
1683 entrysize = offsetof(struct tcp_log_buffer, tlb_th);
1684 error = tcp_log_copyout(sopt, &log_entry->tlm_buf, out_entry,
1688 if (!(log_entry->tlm_buf.tlb_eventflags & TLB_FLAG_HDR)) {
1689 error = tcp_log_copyout(sopt, zerobuf,
1690 ((uint8_t *)out_entry) + entrysize,
1691 sizeof(struct tcp_log_buffer) - entrysize);
1695 * Copy out the verbose bit, if needed. Either way,
1696 * increment the output pointer the correct amount.
1698 if (log_entry->tlm_buf.tlb_eventflags & TLB_FLAG_VERBOSE) {
1699 error = tcp_log_copyout(sopt, &log_entry->tlm_v,
1700 out_entry->tlb_verbose,
1701 sizeof(struct tcp_log_verbose));
1704 out_entry = (struct tcp_log_buffer *)
1705 (((uint8_t *) (out_entry + 1)) +
1706 sizeof(struct tcp_log_verbose));
1711 KASSERT(error || count == 0,
1712 ("%s:%d: Less than expected count (%d) processing list %p"
1713 " (%d remain)", __func__, __LINE__, orig_count,
1714 log_tailqp, count));
1720 * Copy out the buffer. Note that we do incremental copying, so
1721 * sooptcopyout() won't work. However, the goal is to produce the same
1722 * end result as if we copied in the entire user buffer, updated it,
1723 * and then used sooptcopyout() to copy it out.
1725 * NOTE: This should be called with a write lock on the PCB; however,
1726 * the function will drop it after it extracts the data from the TCPCB.
1729 tcp_log_getlogbuf(struct sockopt *sopt, struct tcpcb *tp)
1731 struct tcp_log_stailq log_tailq;
1732 struct tcp_log_mem *log_entry, *log_next;
1733 struct tcp_log_buffer *out_entry;
1735 size_t outsize, entrysize;
1738 INP_WLOCK_ASSERT(tp->t_inpcb);
1742 * Determine which log entries will fit in the buffer. As an
1743 * optimization, skip this if all the entries will clearly fit
1744 * in the buffer. (However, get an exact size if we are using
1748 if (sopt->sopt_valsize / (sizeof(struct tcp_log_buffer) +
1749 sizeof(struct tcp_log_verbose)) >= tp->t_lognum) {
1750 log_entry = STAILQ_LAST(&tp->t_logs, tcp_log_mem, tlm_queue);
1753 outnum = tp->t_lognum;
1756 outsize = outnum = 0;
1758 STAILQ_FOREACH(log_next, &tp->t_logs, tlm_queue) {
1759 entrysize = sizeof(struct tcp_log_buffer);
1760 if (log_next->tlm_buf.tlb_eventflags &
1762 entrysize += sizeof(struct tcp_log_verbose);
1763 if ((sopt->sopt_valsize - outsize) < entrysize)
1765 outsize += entrysize;
1767 log_entry = log_next;
1769 KASSERT(outsize <= sopt->sopt_valsize,
1770 ("%s: calculated output size (%zu) greater than available"
1771 "space (%zu)", __func__, outsize, sopt->sopt_valsize));
1777 * Copy traditional sooptcopyout() behavior: if sopt->sopt_val
1778 * is NULL, silently skip the copy. However, in this case, we
1779 * will leave the list alone and return. Functionally, this
1780 * gives userspace a way to poll for an approximate buffer
1781 * size they will need to get the log entries.
1783 if (sopt->sopt_val == NULL) {
1786 outsize = outnum * (sizeof(struct tcp_log_buffer) +
1787 sizeof(struct tcp_log_verbose));
1789 if (sopt->sopt_valsize > outsize)
1790 sopt->sopt_valsize = outsize;
1795 * Break apart the list. We'll save the ones we want to copy
1796 * out locally and remove them from the TCPCB list. We can
1797 * then drop the INPCB lock while we do the copyout.
1799 * There are roughly three cases:
1800 * 1. There was nothing to copy out. That's easy: drop the
1802 * 2. We are copying out the entire list. Again, that's easy:
1803 * move the whole list.
1804 * 3. We are copying out a partial list. That's harder. We
1805 * need to update the list book-keeping entries.
1807 if (log_entry != NULL && log_next == NULL) {
1808 /* Move entire list. */
1809 KASSERT(outnum == tp->t_lognum,
1810 ("%s:%d: outnum (%d) should match tp->t_lognum (%d)",
1811 __func__, __LINE__, outnum, tp->t_lognum));
1812 log_tailq = tp->t_logs;
1814 STAILQ_INIT(&tp->t_logs);
1815 } else if (log_entry != NULL) {
1816 /* Move partial list. */
1817 KASSERT(outnum < tp->t_lognum,
1818 ("%s:%d: outnum (%d) not less than tp->t_lognum (%d)",
1819 __func__, __LINE__, outnum, tp->t_lognum));
1820 STAILQ_FIRST(&log_tailq) = STAILQ_FIRST(&tp->t_logs);
1821 STAILQ_FIRST(&tp->t_logs) = STAILQ_NEXT(log_entry, tlm_queue);
1822 KASSERT(STAILQ_NEXT(log_entry, tlm_queue) != NULL,
1823 ("%s:%d: tp->t_logs is unexpectedly shorter than expected"
1824 "(tp: %p, log_tailq: %p, outnum: %d, tp->t_lognum: %d)",
1825 __func__, __LINE__, tp, &log_tailq, outnum, tp->t_lognum));
1826 STAILQ_NEXT(log_entry, tlm_queue) = NULL;
1827 log_tailq.stqh_last = &STAILQ_NEXT(log_entry, tlm_queue);
1828 tp->t_lognum -= outnum;
1830 STAILQ_INIT(&log_tailq);
1832 /* Drop the PCB lock. */
1835 /* Copy the data out. */
1836 error = tcp_log_logs_to_buf(sopt, &log_tailq, &out_entry, outnum);
1841 if ((inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) == 0) {
1842 tp = intotcpcb(inp);
1844 /* Merge the two lists. */
1845 STAILQ_CONCAT(&log_tailq, &tp->t_logs);
1846 tp->t_logs = log_tailq;
1847 tp->t_lognum += outnum;
1851 /* Sanity check entries */
1852 KASSERT(((caddr_t)out_entry - (caddr_t)sopt->sopt_val) ==
1853 outsize, ("%s: Actual output size (%zu) != "
1854 "calculated output size (%zu)", __func__,
1855 (size_t)((caddr_t)out_entry - (caddr_t)sopt->sopt_val),
1858 /* Free the entries we just copied out. */
1859 STAILQ_FOREACH_SAFE(log_entry, &log_tailq, tlm_queue, log_next) {
1860 tcp_log_entry_refcnt_rem(log_entry);
1861 uma_zfree(tcp_log_zone, log_entry);
1865 sopt->sopt_valsize = (size_t)((caddr_t)out_entry -
1866 (caddr_t)sopt->sopt_val);
1871 tcp_log_free_queue(struct tcp_log_dev_queue *param)
1873 struct tcp_log_dev_log_queue *entry;
1875 KASSERT(param != NULL, ("%s: called with NULL param", __func__));
1879 entry = (struct tcp_log_dev_log_queue *)param;
1881 /* Free the entries. */
1882 tcp_log_free_entries(&entry->tldl_entries, &entry->tldl_count);
1884 /* Free the buffer, if it is allocated. */
1885 if (entry->tldl_common.tldq_buf != NULL)
1886 free(entry->tldl_common.tldq_buf, M_TCPLOGDEV);
1888 /* Free the queue entry. */
1889 free(entry, M_TCPLOGDEV);
1892 static struct tcp_log_common_header *
1893 tcp_log_expandlogbuf(struct tcp_log_dev_queue *param)
1895 struct tcp_log_dev_log_queue *entry;
1896 struct tcp_log_header *hdr;
1898 struct sockopt sopt;
1901 entry = (struct tcp_log_dev_log_queue *)param;
1903 /* Take a worst-case guess at space needs. */
1904 sopt.sopt_valsize = sizeof(struct tcp_log_header) +
1905 entry->tldl_count * (sizeof(struct tcp_log_buffer) +
1906 sizeof(struct tcp_log_verbose));
1907 hdr = malloc(sopt.sopt_valsize, M_TCPLOGDEV, M_NOWAIT);
1909 #ifdef TCPLOG_DEBUG_COUNTERS
1910 counter_u64_add(tcp_log_que_fail5, entry->tldl_count);
1914 sopt.sopt_val = hdr + 1;
1915 sopt.sopt_valsize -= sizeof(struct tcp_log_header);
1916 sopt.sopt_td = NULL;
1918 error = tcp_log_logs_to_buf(&sopt, &entry->tldl_entries,
1919 (struct tcp_log_buffer **)&end, entry->tldl_count);
1921 free(hdr, M_TCPLOGDEV);
1925 /* Free the entries. */
1926 tcp_log_free_entries(&entry->tldl_entries, &entry->tldl_count);
1927 entry->tldl_count = 0;
1929 memset(hdr, 0, sizeof(struct tcp_log_header));
1930 hdr->tlh_version = TCP_LOG_BUF_VER;
1931 hdr->tlh_type = TCP_LOG_DEV_TYPE_BBR;
1932 hdr->tlh_length = end - (uint8_t *)hdr;
1933 hdr->tlh_ie = entry->tldl_ie;
1934 hdr->tlh_af = entry->tldl_af;
1935 getboottime(&hdr->tlh_offset);
1936 strlcpy(hdr->tlh_id, entry->tldl_id, TCP_LOG_ID_LEN);
1937 strlcpy(hdr->tlh_reason, entry->tldl_reason, TCP_LOG_REASON_LEN);
1938 return ((struct tcp_log_common_header *)hdr);
1942 * Queue the tcpcb's log buffer for transmission via the log buffer facility.
1944 * NOTE: This should be called with a write lock on the PCB.
1946 * how should be M_WAITOK or M_NOWAIT. If M_WAITOK, the function will drop
1947 * and reacquire the INP lock if it needs to do so.
1949 * If force is false, this will only dump auto-logged sessions if
1950 * tcp_log_auto_all is true or if there is a log ID defined for the session.
1953 tcp_log_dump_tp_logbuf(struct tcpcb *tp, char *reason, int how, bool force)
1955 struct tcp_log_dev_log_queue *entry;
1957 #ifdef TCPLOG_DEBUG_COUNTERS
1962 INP_WLOCK_ASSERT(inp);
1964 /* If there are no log entries, there is nothing to do. */
1965 if (tp->t_lognum == 0)
1968 /* Check for a log ID. */
1969 if (tp->t_lib == NULL && (tp->t_flags2 & TF2_LOG_AUTO) &&
1970 !tcp_log_auto_all && !force) {
1971 struct tcp_log_mem *log_entry;
1974 * We needed a log ID and none was found. Free the log entries
1975 * and return success. Also, cancel further logging. If the
1976 * session doesn't have a log ID by now, we'll assume it isn't
1979 while ((log_entry = STAILQ_FIRST(&tp->t_logs)) != NULL)
1980 tcp_log_remove_log_head(tp, log_entry);
1981 KASSERT(tp->t_lognum == 0,
1982 ("%s: After freeing entries, tp->t_lognum=%d (expected 0)",
1983 __func__, tp->t_lognum));
1984 tp->t_logstate = TCP_LOG_STATE_OFF;
1989 * Allocate memory. If we must wait, we'll need to drop the locks
1990 * and reacquire them (and do all the related business that goes
1993 entry = malloc(sizeof(struct tcp_log_dev_log_queue), M_TCPLOGDEV,
1995 if (entry == NULL && (how & M_NOWAIT)) {
1996 #ifdef TCPLOG_DEBUG_COUNTERS
1997 counter_u64_add(tcp_log_que_fail3, 1);
2001 if (entry == NULL) {
2003 entry = malloc(sizeof(struct tcp_log_dev_log_queue),
2004 M_TCPLOGDEV, M_WAITOK);
2007 * Note that this check is slightly overly-restrictive in
2008 * that the TCB can survive either of these events.
2009 * However, there is currently not a good way to ensure
2010 * that is the case. So, if we hit this M_WAIT path, we
2011 * may end up dropping some entries. That seems like a
2012 * small price to pay for safety.
2014 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
2015 free(entry, M_TCPLOGDEV);
2016 #ifdef TCPLOG_DEBUG_COUNTERS
2017 counter_u64_add(tcp_log_que_fail2, 1);
2019 return (ECONNRESET);
2021 tp = intotcpcb(inp);
2022 if (tp->t_lognum == 0) {
2023 free(entry, M_TCPLOGDEV);
2028 /* Fill in the unique parts of the queue entry. */
2029 if (tp->t_lib != NULL)
2030 strlcpy(entry->tldl_id, tp->t_lib->tlb_id, TCP_LOG_ID_LEN);
2032 strlcpy(entry->tldl_id, "UNKNOWN", TCP_LOG_ID_LEN);
2034 strlcpy(entry->tldl_reason, reason, TCP_LOG_REASON_LEN);
2036 strlcpy(entry->tldl_reason, "UNKNOWN", TCP_LOG_ID_LEN);
2037 entry->tldl_ie = inp->inp_inc.inc_ie;
2038 if (inp->inp_inc.inc_flags & INC_ISIPV6)
2039 entry->tldl_af = AF_INET6;
2041 entry->tldl_af = AF_INET;
2042 entry->tldl_entries = tp->t_logs;
2043 entry->tldl_count = tp->t_lognum;
2045 /* Fill in the common parts of the queue entry. */
2046 entry->tldl_common.tldq_buf = NULL;
2047 entry->tldl_common.tldq_xform = tcp_log_expandlogbuf;
2048 entry->tldl_common.tldq_dtor = tcp_log_free_queue;
2050 /* Clear the log data from the TCPCB. */
2051 #ifdef TCPLOG_DEBUG_COUNTERS
2052 num_entries = tp->t_lognum;
2055 STAILQ_INIT(&tp->t_logs);
2057 /* Add the entry. If no one is listening, free the entry. */
2058 if (tcp_log_dev_add_log((struct tcp_log_dev_queue *)entry)) {
2059 tcp_log_free_queue((struct tcp_log_dev_queue *)entry);
2060 #ifdef TCPLOG_DEBUG_COUNTERS
2061 counter_u64_add(tcp_log_que_fail1, num_entries);
2063 counter_u64_add(tcp_log_queued, num_entries);
2070 * Queue the log_id_node's log buffers for transmission via the log buffer
2073 * NOTE: This should be called with the bucket locked and referenced.
2075 * how should be M_WAITOK or M_NOWAIT. If M_WAITOK, the function will drop
2076 * and reacquire the bucket lock if it needs to do so. (The caller must
2077 * ensure that the tln is no longer on any lists so no one else will mess
2078 * with this while the lock is dropped!)
2081 tcp_log_dump_node_logbuf(struct tcp_log_id_node *tln, char *reason, int how)
2083 struct tcp_log_dev_log_queue *entry;
2084 struct tcp_log_id_bucket *tlb;
2086 tlb = tln->tln_bucket;
2087 TCPID_BUCKET_LOCK_ASSERT(tlb);
2088 KASSERT(tlb->tlb_refcnt > 0,
2089 ("%s:%d: Called with unreferenced bucket (tln=%p, tlb=%p)",
2090 __func__, __LINE__, tln, tlb));
2091 KASSERT(tln->tln_closed,
2092 ("%s:%d: Called for node with tln_closed==false (tln=%p)",
2093 __func__, __LINE__, tln));
2095 /* If there are no log entries, there is nothing to do. */
2096 if (tln->tln_count == 0)
2100 * Allocate memory. If we must wait, we'll need to drop the locks
2101 * and reacquire them (and do all the related business that goes
2104 entry = malloc(sizeof(struct tcp_log_dev_log_queue), M_TCPLOGDEV,
2106 if (entry == NULL && (how & M_NOWAIT))
2108 if (entry == NULL) {
2109 TCPID_BUCKET_UNLOCK(tlb);
2110 entry = malloc(sizeof(struct tcp_log_dev_log_queue),
2111 M_TCPLOGDEV, M_WAITOK);
2112 TCPID_BUCKET_LOCK(tlb);
2115 /* Fill in the common parts of the queue entry.. */
2116 entry->tldl_common.tldq_buf = NULL;
2117 entry->tldl_common.tldq_xform = tcp_log_expandlogbuf;
2118 entry->tldl_common.tldq_dtor = tcp_log_free_queue;
2120 /* Fill in the unique parts of the queue entry. */
2121 strlcpy(entry->tldl_id, tlb->tlb_id, TCP_LOG_ID_LEN);
2123 strlcpy(entry->tldl_reason, reason, TCP_LOG_REASON_LEN);
2125 strlcpy(entry->tldl_reason, "UNKNOWN", TCP_LOG_ID_LEN);
2126 entry->tldl_ie = tln->tln_ie;
2127 entry->tldl_entries = tln->tln_entries;
2128 entry->tldl_count = tln->tln_count;
2129 entry->tldl_af = tln->tln_af;
2131 /* Add the entry. If no one is listening, free the entry. */
2132 if (tcp_log_dev_add_log((struct tcp_log_dev_queue *)entry))
2133 tcp_log_free_queue((struct tcp_log_dev_queue *)entry);
2140 * Queue the log buffers for all sessions in a bucket for transmissions via
2141 * the log buffer facility.
2143 * NOTE: This should be called with a locked bucket; however, the function
2144 * will drop the lock.
2146 #define LOCAL_SAVE 10
2148 tcp_log_dumpbucketlogs(struct tcp_log_id_bucket *tlb, char *reason)
2150 struct tcp_log_id_node local_entries[LOCAL_SAVE];
2153 struct tcp_log_id_node *cur_tln, *prev_tln, *tmp_tln;
2154 int i, num_local_entries, tree_locked;
2155 bool expireq_locked;
2157 TCPID_BUCKET_LOCK_ASSERT(tlb);
2160 * Take a reference on the bucket to keep it from disappearing until
2163 TCPID_BUCKET_REF(tlb);
2166 * We'll try to create these without dropping locks. However, we
2167 * might very well need to drop locks to get memory. If that's the
2168 * case, we'll save up to 10 on the stack, and sacrifice the rest.
2169 * (Otherwise, we need to worry about finding our place again in a
2170 * potentially changed list. It just doesn't seem worth the trouble
2173 expireq_locked = false;
2174 num_local_entries = 0;
2176 tree_locked = TREE_UNLOCKED;
2177 SLIST_FOREACH_SAFE(cur_tln, &tlb->tlb_head, tln_list, tmp_tln) {
2179 * If this isn't associated with a TCPCB, we can pull it off
2180 * the list now. We need to be careful that the expire timer
2181 * hasn't already taken ownership (tln_expiretime == SBT_MAX).
2182 * If so, we let the expire timer code free the data.
2184 if (cur_tln->tln_closed) {
2187 * Get the expireq lock so we can get a consistent
2188 * read of tln_expiretime and so we can remove this
2191 if (!expireq_locked) {
2192 TCPLOG_EXPIREQ_LOCK();
2193 expireq_locked = true;
2197 * We ignore entries with tln_expiretime == SBT_MAX.
2198 * The expire timer code already owns those.
2200 KASSERT(cur_tln->tln_expiretime > (sbintime_t) 0,
2201 ("%s:%d: node on the expire queue without positive "
2202 "expire time", __func__, __LINE__));
2203 if (cur_tln->tln_expiretime == SBT_MAX) {
2208 /* Remove the entry from the expireq. */
2209 STAILQ_REMOVE(&tcp_log_expireq_head, cur_tln,
2210 tcp_log_id_node, tln_expireq);
2212 /* Remove the entry from the bucket. */
2213 if (prev_tln != NULL)
2214 SLIST_REMOVE_AFTER(prev_tln, tln_list);
2216 SLIST_REMOVE_HEAD(&tlb->tlb_head, tln_list);
2219 * Drop the INP and bucket reference counts. Due to
2220 * lock-ordering rules, we need to drop the expire
2223 TCPLOG_EXPIREQ_UNLOCK();
2224 expireq_locked = false;
2226 /* Drop the INP reference. */
2227 INP_WLOCK(cur_tln->tln_inp);
2228 if (!in_pcbrele_wlocked(cur_tln->tln_inp))
2229 INP_WUNLOCK(cur_tln->tln_inp);
2231 if (tcp_log_unref_bucket(tlb, &tree_locked, NULL)) {
2233 panic("%s: Bucket refcount unexpectedly 0.",
2237 * Recover as best we can: free the entry we
2240 tcp_log_free_entries(&cur_tln->tln_entries,
2241 &cur_tln->tln_count);
2242 uma_zfree(tcp_log_node_zone, cur_tln);
2246 if (tcp_log_dump_node_logbuf(cur_tln, reason,
2249 * If we have sapce, save the entries locally.
2250 * Otherwise, free them.
2252 if (num_local_entries < LOCAL_SAVE) {
2253 local_entries[num_local_entries] =
2255 num_local_entries++;
2257 tcp_log_free_entries(
2258 &cur_tln->tln_entries,
2259 &cur_tln->tln_count);
2263 /* No matter what, we are done with the node now. */
2264 uma_zfree(tcp_log_node_zone, cur_tln);
2267 * Because we removed this entry from the list, prev_tln
2268 * (which tracks the previous entry still on the tlb
2269 * list) remains unchanged.
2275 * If we get to this point, the session data is still held in
2276 * the TCPCB. So, we need to pull the data out of that.
2278 * We will need to drop the expireq lock so we can lock the INP.
2279 * We can then try to extract the data the "easy" way. If that
2280 * fails, we'll save the log entries for later.
2282 if (expireq_locked) {
2283 TCPLOG_EXPIREQ_UNLOCK();
2284 expireq_locked = false;
2287 /* Lock the INP and then re-check the state. */
2288 inp = cur_tln->tln_inp;
2291 * If we caught this while it was transitioning, the data
2292 * might have moved from the TCPCB to the tln (signified by
2293 * setting tln_closed to true. If so, treat this like an
2294 * inactive connection.
2296 if (cur_tln->tln_closed) {
2298 * It looks like we may have caught this connection
2299 * while it was transitioning from active to inactive.
2300 * Treat this like an inactive connection.
2307 * Try to dump the data from the tp without dropping the lock.
2308 * If this fails, try to save off the data locally.
2310 tp = cur_tln->tln_tp;
2311 if (tcp_log_dump_tp_logbuf(tp, reason, M_NOWAIT, true) &&
2312 num_local_entries < LOCAL_SAVE) {
2313 tcp_log_move_tp_to_node(tp,
2314 &local_entries[num_local_entries]);
2315 local_entries[num_local_entries].tln_closed = 1;
2316 KASSERT(local_entries[num_local_entries].tln_bucket ==
2317 tlb, ("%s: %d: bucket mismatch for node %p",
2318 __func__, __LINE__, cur_tln));
2319 num_local_entries++;
2325 * We are goint to leave the current tln on the list. It will
2326 * become the previous tln.
2331 /* Drop our locks, if any. */
2332 KASSERT(tree_locked == TREE_UNLOCKED,
2333 ("%s: %d: tree unexpectedly locked", __func__, __LINE__));
2334 switch (tree_locked) {
2336 TCPID_TREE_WUNLOCK();
2337 tree_locked = TREE_UNLOCKED;
2340 TCPID_TREE_RUNLOCK();
2341 tree_locked = TREE_UNLOCKED;
2344 if (expireq_locked) {
2345 TCPLOG_EXPIREQ_UNLOCK();
2346 expireq_locked = false;
2350 * Try again for any saved entries. tcp_log_dump_node_logbuf() is
2351 * guaranteed to free the log entries within the node. And, since
2352 * the node itself is on our stack, we don't need to free it.
2354 for (i = 0; i < num_local_entries; i++)
2355 tcp_log_dump_node_logbuf(&local_entries[i], reason, M_WAITOK);
2357 /* Drop our reference. */
2358 if (!tcp_log_unref_bucket(tlb, &tree_locked, NULL))
2359 TCPID_BUCKET_UNLOCK(tlb);
2362 /* Drop our locks, if any. */
2363 switch (tree_locked) {
2365 TCPID_TREE_WUNLOCK();
2368 TCPID_TREE_RUNLOCK();
2372 TCPLOG_EXPIREQ_UNLOCK();
2378 * Queue the log buffers for all sessions in a bucket for transmissions via
2379 * the log buffer facility.
2381 * NOTE: This should be called with a locked INP; however, the function
2382 * will drop the lock.
2385 tcp_log_dump_tp_bucket_logbufs(struct tcpcb *tp, char *reason)
2387 struct tcp_log_id_bucket *tlb;
2390 /* Figure out our bucket and lock it. */
2391 INP_WLOCK_ASSERT(tp->t_inpcb);
2395 * No bucket; treat this like a request to dump a single
2398 (void)tcp_log_dump_tp_logbuf(tp, reason, M_WAITOK, true);
2399 INP_WUNLOCK(tp->t_inpcb);
2402 TCPID_BUCKET_REF(tlb);
2403 INP_WUNLOCK(tp->t_inpcb);
2404 TCPID_BUCKET_LOCK(tlb);
2406 /* If we are the last reference, we have nothing more to do here. */
2407 tree_locked = TREE_UNLOCKED;
2408 if (tcp_log_unref_bucket(tlb, &tree_locked, NULL)) {
2409 switch (tree_locked) {
2411 TCPID_TREE_WUNLOCK();
2414 TCPID_TREE_RUNLOCK();
2420 /* Turn this over to tcp_log_dumpbucketlogs() to finish the work. */
2421 tcp_log_dumpbucketlogs(tlb, reason);
2425 * Mark the end of a flow with the current stack. A stack can add
2426 * stack-specific info to this trace event by overriding this
2427 * function (see bbr_log_flowend() for example).
2430 tcp_log_flowend(struct tcpcb *tp)
2432 if (tp->t_logstate != TCP_LOG_STATE_OFF) {
2433 struct socket *so = tp->t_inpcb->inp_socket;
2434 TCP_LOG_EVENT(tp, NULL, &so->so_rcv, &so->so_snd,
2435 TCP_LOG_FLOWEND, 0, 0, NULL, false);