1 #include <linux/rcupdate.h>
2 #include <linux/spinlock.h>
3 #include <linux/jiffies.h>
4 #include <linux/module.h>
5 #include <linux/cache.h>
6 #include <linux/slab.h>
7 #include <linux/init.h>
9 #include <linux/hash.h>
10 #include <linux/tcp_metrics.h>
11 #include <linux/vmalloc.h>
13 #include <net/inet_connection_sock.h>
14 #include <net/net_namespace.h>
15 #include <net/request_sock.h>
16 #include <net/inetpeer.h>
21 #include <net/genetlink.h>
23 int sysctl_tcp_nometrics_save __read_mostly
;
25 struct tcp_fastopen_metrics
{
27 u16 syn_loss
:10; /* Recurring Fast Open SYN losses */
28 unsigned long last_syn_loss
; /* Last Fast Open SYN loss */
29 struct tcp_fastopen_cookie cookie
;
32 struct tcp_metrics_block
{
33 struct tcp_metrics_block __rcu
*tcpm_next
;
34 struct inetpeer_addr tcpm_saddr
;
35 struct inetpeer_addr tcpm_daddr
;
36 unsigned long tcpm_stamp
;
40 u32 tcpm_vals
[TCP_METRIC_MAX
+ 1];
41 struct tcp_fastopen_metrics tcpm_fastopen
;
43 struct rcu_head rcu_head
;
46 static bool tcp_metric_locked(struct tcp_metrics_block
*tm
,
47 enum tcp_metric_index idx
)
49 return tm
->tcpm_lock
& (1 << idx
);
52 static u32
tcp_metric_get(struct tcp_metrics_block
*tm
,
53 enum tcp_metric_index idx
)
55 return tm
->tcpm_vals
[idx
];
58 static u32
tcp_metric_get_jiffies(struct tcp_metrics_block
*tm
,
59 enum tcp_metric_index idx
)
61 return msecs_to_jiffies(tm
->tcpm_vals
[idx
]);
64 static void tcp_metric_set(struct tcp_metrics_block
*tm
,
65 enum tcp_metric_index idx
,
68 tm
->tcpm_vals
[idx
] = val
;
71 static void tcp_metric_set_msecs(struct tcp_metrics_block
*tm
,
72 enum tcp_metric_index idx
,
75 tm
->tcpm_vals
[idx
] = jiffies_to_msecs(val
);
78 static bool addr_same(const struct inetpeer_addr
*a
,
79 const struct inetpeer_addr
*b
)
81 const struct in6_addr
*a6
, *b6
;
83 if (a
->family
!= b
->family
)
85 if (a
->family
== AF_INET
)
86 return a
->addr
.a4
== b
->addr
.a4
;
88 a6
= (const struct in6_addr
*) &a
->addr
.a6
[0];
89 b6
= (const struct in6_addr
*) &b
->addr
.a6
[0];
91 return ipv6_addr_equal(a6
, b6
);
94 struct tcpm_hash_bucket
{
95 struct tcp_metrics_block __rcu
*chain
;
98 static DEFINE_SPINLOCK(tcp_metrics_lock
);
100 static void tcpm_suck_dst(struct tcp_metrics_block
*tm
, struct dst_entry
*dst
,
105 tm
->tcpm_stamp
= jiffies
;
108 if (dst_metric_locked(dst
, RTAX_RTT
))
109 val
|= 1 << TCP_METRIC_RTT
;
110 if (dst_metric_locked(dst
, RTAX_RTTVAR
))
111 val
|= 1 << TCP_METRIC_RTTVAR
;
112 if (dst_metric_locked(dst
, RTAX_SSTHRESH
))
113 val
|= 1 << TCP_METRIC_SSTHRESH
;
114 if (dst_metric_locked(dst
, RTAX_CWND
))
115 val
|= 1 << TCP_METRIC_CWND
;
116 if (dst_metric_locked(dst
, RTAX_REORDERING
))
117 val
|= 1 << TCP_METRIC_REORDERING
;
120 tm
->tcpm_vals
[TCP_METRIC_RTT
] = dst_metric_raw(dst
, RTAX_RTT
);
121 tm
->tcpm_vals
[TCP_METRIC_RTTVAR
] = dst_metric_raw(dst
, RTAX_RTTVAR
);
122 tm
->tcpm_vals
[TCP_METRIC_SSTHRESH
] = dst_metric_raw(dst
, RTAX_SSTHRESH
);
123 tm
->tcpm_vals
[TCP_METRIC_CWND
] = dst_metric_raw(dst
, RTAX_CWND
);
124 tm
->tcpm_vals
[TCP_METRIC_REORDERING
] = dst_metric_raw(dst
, RTAX_REORDERING
);
126 tm
->tcpm_ts_stamp
= 0;
127 if (fastopen_clear
) {
128 tm
->tcpm_fastopen
.mss
= 0;
129 tm
->tcpm_fastopen
.syn_loss
= 0;
130 tm
->tcpm_fastopen
.cookie
.len
= 0;
134 static struct tcp_metrics_block
*tcpm_new(struct dst_entry
*dst
,
135 struct inetpeer_addr
*saddr
,
136 struct inetpeer_addr
*daddr
,
140 struct tcp_metrics_block
*tm
;
143 spin_lock_bh(&tcp_metrics_lock
);
144 net
= dev_net(dst
->dev
);
145 if (unlikely(reclaim
)) {
146 struct tcp_metrics_block
*oldest
;
148 oldest
= rcu_dereference(net
->ipv4
.tcp_metrics_hash
[hash
].chain
);
149 for (tm
= rcu_dereference(oldest
->tcpm_next
); tm
;
150 tm
= rcu_dereference(tm
->tcpm_next
)) {
151 if (time_before(tm
->tcpm_stamp
, oldest
->tcpm_stamp
))
156 tm
= kmalloc(sizeof(*tm
), GFP_ATOMIC
);
160 tm
->tcpm_saddr
= *saddr
;
161 tm
->tcpm_daddr
= *daddr
;
163 tcpm_suck_dst(tm
, dst
, true);
165 if (likely(!reclaim
)) {
166 tm
->tcpm_next
= net
->ipv4
.tcp_metrics_hash
[hash
].chain
;
167 rcu_assign_pointer(net
->ipv4
.tcp_metrics_hash
[hash
].chain
, tm
);
171 spin_unlock_bh(&tcp_metrics_lock
);
175 #define TCP_METRICS_TIMEOUT (60 * 60 * HZ)
177 static void tcpm_check_stamp(struct tcp_metrics_block
*tm
, struct dst_entry
*dst
)
179 if (tm
&& unlikely(time_after(jiffies
, tm
->tcpm_stamp
+ TCP_METRICS_TIMEOUT
)))
180 tcpm_suck_dst(tm
, dst
, false);
183 #define TCP_METRICS_RECLAIM_DEPTH 5
184 #define TCP_METRICS_RECLAIM_PTR (struct tcp_metrics_block *) 0x1UL
186 static struct tcp_metrics_block
*tcp_get_encode(struct tcp_metrics_block
*tm
, int depth
)
190 if (depth
> TCP_METRICS_RECLAIM_DEPTH
)
191 return TCP_METRICS_RECLAIM_PTR
;
195 static struct tcp_metrics_block
*__tcp_get_metrics(const struct inetpeer_addr
*saddr
,
196 const struct inetpeer_addr
*daddr
,
197 struct net
*net
, unsigned int hash
)
199 struct tcp_metrics_block
*tm
;
202 for (tm
= rcu_dereference(net
->ipv4
.tcp_metrics_hash
[hash
].chain
); tm
;
203 tm
= rcu_dereference(tm
->tcpm_next
)) {
204 if (addr_same(&tm
->tcpm_saddr
, saddr
) &&
205 addr_same(&tm
->tcpm_daddr
, daddr
))
209 return tcp_get_encode(tm
, depth
);
212 static struct tcp_metrics_block
*__tcp_get_metrics_req(struct request_sock
*req
,
213 struct dst_entry
*dst
)
215 struct tcp_metrics_block
*tm
;
216 struct inetpeer_addr saddr
, daddr
;
220 saddr
.family
= req
->rsk_ops
->family
;
221 daddr
.family
= req
->rsk_ops
->family
;
222 switch (daddr
.family
) {
224 saddr
.addr
.a4
= inet_rsk(req
)->ir_loc_addr
;
225 daddr
.addr
.a4
= inet_rsk(req
)->ir_rmt_addr
;
226 hash
= (__force
unsigned int) daddr
.addr
.a4
;
228 #if IS_ENABLED(CONFIG_IPV6)
230 *(struct in6_addr
*)saddr
.addr
.a6
= inet_rsk(req
)->ir_v6_loc_addr
;
231 *(struct in6_addr
*)daddr
.addr
.a6
= inet_rsk(req
)->ir_v6_rmt_addr
;
232 hash
= ipv6_addr_hash(&inet_rsk(req
)->ir_v6_rmt_addr
);
239 net
= dev_net(dst
->dev
);
240 hash
= hash_32(hash
, net
->ipv4
.tcp_metrics_hash_log
);
242 for (tm
= rcu_dereference(net
->ipv4
.tcp_metrics_hash
[hash
].chain
); tm
;
243 tm
= rcu_dereference(tm
->tcpm_next
)) {
244 if (addr_same(&tm
->tcpm_saddr
, &saddr
) &&
245 addr_same(&tm
->tcpm_daddr
, &daddr
))
248 tcpm_check_stamp(tm
, dst
);
252 static struct tcp_metrics_block
*__tcp_get_metrics_tw(struct inet_timewait_sock
*tw
)
254 struct tcp_metrics_block
*tm
;
255 struct inetpeer_addr saddr
, daddr
;
259 saddr
.family
= tw
->tw_family
;
260 daddr
.family
= tw
->tw_family
;
261 switch (daddr
.family
) {
263 saddr
.addr
.a4
= tw
->tw_rcv_saddr
;
264 daddr
.addr
.a4
= tw
->tw_daddr
;
265 hash
= (__force
unsigned int) daddr
.addr
.a4
;
267 #if IS_ENABLED(CONFIG_IPV6)
269 *(struct in6_addr
*)saddr
.addr
.a6
= tw
->tw_v6_rcv_saddr
;
270 *(struct in6_addr
*)daddr
.addr
.a6
= tw
->tw_v6_daddr
;
271 hash
= ipv6_addr_hash(&tw
->tw_v6_daddr
);
279 hash
= hash_32(hash
, net
->ipv4
.tcp_metrics_hash_log
);
281 for (tm
= rcu_dereference(net
->ipv4
.tcp_metrics_hash
[hash
].chain
); tm
;
282 tm
= rcu_dereference(tm
->tcpm_next
)) {
283 if (addr_same(&tm
->tcpm_saddr
, &saddr
) &&
284 addr_same(&tm
->tcpm_daddr
, &daddr
))
290 static struct tcp_metrics_block
*tcp_get_metrics(struct sock
*sk
,
291 struct dst_entry
*dst
,
294 struct tcp_metrics_block
*tm
;
295 struct inetpeer_addr saddr
, daddr
;
300 saddr
.family
= sk
->sk_family
;
301 daddr
.family
= sk
->sk_family
;
302 switch (daddr
.family
) {
304 saddr
.addr
.a4
= inet_sk(sk
)->inet_saddr
;
305 daddr
.addr
.a4
= inet_sk(sk
)->inet_daddr
;
306 hash
= (__force
unsigned int) daddr
.addr
.a4
;
308 #if IS_ENABLED(CONFIG_IPV6)
310 *(struct in6_addr
*)saddr
.addr
.a6
= sk
->sk_v6_rcv_saddr
;
311 *(struct in6_addr
*)daddr
.addr
.a6
= sk
->sk_v6_daddr
;
312 hash
= ipv6_addr_hash(&sk
->sk_v6_daddr
);
319 net
= dev_net(dst
->dev
);
320 hash
= hash_32(hash
, net
->ipv4
.tcp_metrics_hash_log
);
322 tm
= __tcp_get_metrics(&saddr
, &daddr
, net
, hash
);
324 if (tm
== TCP_METRICS_RECLAIM_PTR
) {
329 tm
= tcpm_new(dst
, &saddr
, &daddr
, hash
, reclaim
);
331 tcpm_check_stamp(tm
, dst
);
336 /* Save metrics learned by this TCP session. This function is called
337 * only, when TCP finishes successfully i.e. when it enters TIME-WAIT
338 * or goes from LAST-ACK to CLOSE.
340 void tcp_update_metrics(struct sock
*sk
)
342 const struct inet_connection_sock
*icsk
= inet_csk(sk
);
343 struct dst_entry
*dst
= __sk_dst_get(sk
);
344 struct tcp_sock
*tp
= tcp_sk(sk
);
345 struct tcp_metrics_block
*tm
;
350 if (sysctl_tcp_nometrics_save
|| !dst
)
353 if (dst
->flags
& DST_HOST
)
357 if (icsk
->icsk_backoff
|| !tp
->srtt
) {
358 /* This session failed to estimate rtt. Why?
359 * Probably, no packets returned in time. Reset our
362 tm
= tcp_get_metrics(sk
, dst
, false);
363 if (tm
&& !tcp_metric_locked(tm
, TCP_METRIC_RTT
))
364 tcp_metric_set(tm
, TCP_METRIC_RTT
, 0);
367 tm
= tcp_get_metrics(sk
, dst
, true);
372 rtt
= tcp_metric_get_jiffies(tm
, TCP_METRIC_RTT
);
375 /* If newly calculated rtt larger than stored one, store new
376 * one. Otherwise, use EWMA. Remember, rtt overestimation is
377 * always better than underestimation.
379 if (!tcp_metric_locked(tm
, TCP_METRIC_RTT
)) {
384 tcp_metric_set_msecs(tm
, TCP_METRIC_RTT
, rtt
);
387 if (!tcp_metric_locked(tm
, TCP_METRIC_RTTVAR
)) {
393 /* Scale deviation to rttvar fixed point */
398 var
= tcp_metric_get_jiffies(tm
, TCP_METRIC_RTTVAR
);
402 var
-= (var
- m
) >> 2;
404 tcp_metric_set_msecs(tm
, TCP_METRIC_RTTVAR
, var
);
407 if (tcp_in_initial_slowstart(tp
)) {
408 /* Slow start still did not finish. */
409 if (!tcp_metric_locked(tm
, TCP_METRIC_SSTHRESH
)) {
410 val
= tcp_metric_get(tm
, TCP_METRIC_SSTHRESH
);
411 if (val
&& (tp
->snd_cwnd
>> 1) > val
)
412 tcp_metric_set(tm
, TCP_METRIC_SSTHRESH
,
415 if (!tcp_metric_locked(tm
, TCP_METRIC_CWND
)) {
416 val
= tcp_metric_get(tm
, TCP_METRIC_CWND
);
417 if (tp
->snd_cwnd
> val
)
418 tcp_metric_set(tm
, TCP_METRIC_CWND
,
421 } else if (tp
->snd_cwnd
> tp
->snd_ssthresh
&&
422 icsk
->icsk_ca_state
== TCP_CA_Open
) {
423 /* Cong. avoidance phase, cwnd is reliable. */
424 if (!tcp_metric_locked(tm
, TCP_METRIC_SSTHRESH
))
425 tcp_metric_set(tm
, TCP_METRIC_SSTHRESH
,
426 max(tp
->snd_cwnd
>> 1, tp
->snd_ssthresh
));
427 if (!tcp_metric_locked(tm
, TCP_METRIC_CWND
)) {
428 val
= tcp_metric_get(tm
, TCP_METRIC_CWND
);
429 tcp_metric_set(tm
, TCP_METRIC_CWND
, (val
+ tp
->snd_cwnd
) >> 1);
432 /* Else slow start did not finish, cwnd is non-sense,
433 * ssthresh may be also invalid.
435 if (!tcp_metric_locked(tm
, TCP_METRIC_CWND
)) {
436 val
= tcp_metric_get(tm
, TCP_METRIC_CWND
);
437 tcp_metric_set(tm
, TCP_METRIC_CWND
,
438 (val
+ tp
->snd_ssthresh
) >> 1);
440 if (!tcp_metric_locked(tm
, TCP_METRIC_SSTHRESH
)) {
441 val
= tcp_metric_get(tm
, TCP_METRIC_SSTHRESH
);
442 if (val
&& tp
->snd_ssthresh
> val
)
443 tcp_metric_set(tm
, TCP_METRIC_SSTHRESH
,
446 if (!tcp_metric_locked(tm
, TCP_METRIC_REORDERING
)) {
447 val
= tcp_metric_get(tm
, TCP_METRIC_REORDERING
);
448 if (val
< tp
->reordering
&&
449 tp
->reordering
!= sysctl_tcp_reordering
)
450 tcp_metric_set(tm
, TCP_METRIC_REORDERING
,
454 tm
->tcpm_stamp
= jiffies
;
459 /* Initialize metrics on socket. */
461 void tcp_init_metrics(struct sock
*sk
)
463 struct dst_entry
*dst
= __sk_dst_get(sk
);
464 struct tcp_sock
*tp
= tcp_sk(sk
);
465 struct tcp_metrics_block
*tm
;
466 u32 val
, crtt
= 0; /* cached RTT scaled by 8 */
474 tm
= tcp_get_metrics(sk
, dst
, true);
480 if (tcp_metric_locked(tm
, TCP_METRIC_CWND
))
481 tp
->snd_cwnd_clamp
= tcp_metric_get(tm
, TCP_METRIC_CWND
);
483 val
= tcp_metric_get(tm
, TCP_METRIC_SSTHRESH
);
485 tp
->snd_ssthresh
= val
;
486 if (tp
->snd_ssthresh
> tp
->snd_cwnd_clamp
)
487 tp
->snd_ssthresh
= tp
->snd_cwnd_clamp
;
489 /* ssthresh may have been reduced unnecessarily during.
490 * 3WHS. Restore it back to its initial default.
492 tp
->snd_ssthresh
= TCP_INFINITE_SSTHRESH
;
494 val
= tcp_metric_get(tm
, TCP_METRIC_REORDERING
);
495 if (val
&& tp
->reordering
!= val
) {
496 tcp_disable_fack(tp
);
497 tcp_disable_early_retrans(tp
);
498 tp
->reordering
= val
;
501 crtt
= tcp_metric_get_jiffies(tm
, TCP_METRIC_RTT
);
504 /* The initial RTT measurement from the SYN/SYN-ACK is not ideal
505 * to seed the RTO for later data packets because SYN packets are
506 * small. Use the per-dst cached values to seed the RTO but keep
507 * the RTT estimator variables intact (e.g., srtt, mdev, rttvar).
508 * Later the RTO will be updated immediately upon obtaining the first
509 * data RTT sample (tcp_rtt_estimator()). Hence the cached RTT only
510 * influences the first RTO but not later RTT estimation.
512 * But if RTT is not available from the SYN (due to retransmits or
513 * syn cookies) or the cache, force a conservative 3secs timeout.
515 * A bit of theory. RTT is time passed after "normal" sized packet
516 * is sent until it is ACKed. In normal circumstances sending small
517 * packets force peer to delay ACKs and calculation is correct too.
518 * The algorithm is adaptive and, provided we follow specs, it
519 * NEVER underestimate RTT. BUT! If peer tries to make some clever
520 * tricks sort of "quick acks" for time long enough to decrease RTT
521 * to low value, and then abruptly stops to do it and starts to delay
522 * ACKs, wait for troubles.
524 if (crtt
> tp
->srtt
) {
525 /* Set RTO like tcp_rtt_estimator(), but from cached RTT. */
527 inet_csk(sk
)->icsk_rto
= crtt
+ max(2 * crtt
, tcp_rto_min(sk
));
528 } else if (tp
->srtt
== 0) {
529 /* RFC6298: 5.7 We've failed to get a valid RTT sample from
530 * 3WHS. This is most likely due to retransmission,
531 * including spurious one. Reset the RTO back to 3secs
532 * from the more aggressive 1sec to avoid more spurious
535 tp
->mdev
= tp
->mdev_max
= tp
->rttvar
= TCP_TIMEOUT_FALLBACK
;
536 inet_csk(sk
)->icsk_rto
= TCP_TIMEOUT_FALLBACK
;
538 /* Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been
539 * retransmitted. In light of RFC6298 more aggressive 1sec
540 * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK
541 * retransmission has occurred.
543 if (tp
->total_retrans
> 1)
546 tp
->snd_cwnd
= tcp_init_cwnd(tp
, dst
);
547 tp
->snd_cwnd_stamp
= tcp_time_stamp
;
550 bool tcp_peer_is_proven(struct request_sock
*req
, struct dst_entry
*dst
, bool paws_check
)
552 struct tcp_metrics_block
*tm
;
559 tm
= __tcp_get_metrics_req(req
, dst
);
562 (u32
)get_seconds() - tm
->tcpm_ts_stamp
< TCP_PAWS_MSL
&&
563 (s32
)(tm
->tcpm_ts
- req
->ts_recent
) > TCP_PAWS_WINDOW
)
568 if (tm
&& tcp_metric_get(tm
, TCP_METRIC_RTT
) && tm
->tcpm_ts_stamp
)
577 EXPORT_SYMBOL_GPL(tcp_peer_is_proven
);
579 void tcp_fetch_timewait_stamp(struct sock
*sk
, struct dst_entry
*dst
)
581 struct tcp_metrics_block
*tm
;
584 tm
= tcp_get_metrics(sk
, dst
, true);
586 struct tcp_sock
*tp
= tcp_sk(sk
);
588 if ((u32
)get_seconds() - tm
->tcpm_ts_stamp
<= TCP_PAWS_MSL
) {
589 tp
->rx_opt
.ts_recent_stamp
= tm
->tcpm_ts_stamp
;
590 tp
->rx_opt
.ts_recent
= tm
->tcpm_ts
;
595 EXPORT_SYMBOL_GPL(tcp_fetch_timewait_stamp
);
597 /* VJ's idea. Save last timestamp seen from this destination and hold
598 * it at least for normal timewait interval to use for duplicate
599 * segment detection in subsequent connections, before they enter
600 * synchronized state.
602 bool tcp_remember_stamp(struct sock
*sk
)
604 struct dst_entry
*dst
= __sk_dst_get(sk
);
608 struct tcp_metrics_block
*tm
;
611 tm
= tcp_get_metrics(sk
, dst
, true);
613 struct tcp_sock
*tp
= tcp_sk(sk
);
615 if ((s32
)(tm
->tcpm_ts
- tp
->rx_opt
.ts_recent
) <= 0 ||
616 ((u32
)get_seconds() - tm
->tcpm_ts_stamp
> TCP_PAWS_MSL
&&
617 tm
->tcpm_ts_stamp
<= (u32
)tp
->rx_opt
.ts_recent_stamp
)) {
618 tm
->tcpm_ts_stamp
= (u32
)tp
->rx_opt
.ts_recent_stamp
;
619 tm
->tcpm_ts
= tp
->rx_opt
.ts_recent
;
628 bool tcp_tw_remember_stamp(struct inet_timewait_sock
*tw
)
630 struct tcp_metrics_block
*tm
;
634 tm
= __tcp_get_metrics_tw(tw
);
636 const struct tcp_timewait_sock
*tcptw
;
637 struct sock
*sk
= (struct sock
*) tw
;
639 tcptw
= tcp_twsk(sk
);
640 if ((s32
)(tm
->tcpm_ts
- tcptw
->tw_ts_recent
) <= 0 ||
641 ((u32
)get_seconds() - tm
->tcpm_ts_stamp
> TCP_PAWS_MSL
&&
642 tm
->tcpm_ts_stamp
<= (u32
)tcptw
->tw_ts_recent_stamp
)) {
643 tm
->tcpm_ts_stamp
= (u32
)tcptw
->tw_ts_recent_stamp
;
644 tm
->tcpm_ts
= tcptw
->tw_ts_recent
;
653 static DEFINE_SEQLOCK(fastopen_seqlock
);
655 void tcp_fastopen_cache_get(struct sock
*sk
, u16
*mss
,
656 struct tcp_fastopen_cookie
*cookie
,
657 int *syn_loss
, unsigned long *last_syn_loss
)
659 struct tcp_metrics_block
*tm
;
662 tm
= tcp_get_metrics(sk
, __sk_dst_get(sk
), false);
664 struct tcp_fastopen_metrics
*tfom
= &tm
->tcpm_fastopen
;
668 seq
= read_seqbegin(&fastopen_seqlock
);
671 *cookie
= tfom
->cookie
;
672 *syn_loss
= tfom
->syn_loss
;
673 *last_syn_loss
= *syn_loss
? tfom
->last_syn_loss
: 0;
674 } while (read_seqretry(&fastopen_seqlock
, seq
));
679 void tcp_fastopen_cache_set(struct sock
*sk
, u16 mss
,
680 struct tcp_fastopen_cookie
*cookie
, bool syn_lost
)
682 struct dst_entry
*dst
= __sk_dst_get(sk
);
683 struct tcp_metrics_block
*tm
;
688 tm
= tcp_get_metrics(sk
, dst
, true);
690 struct tcp_fastopen_metrics
*tfom
= &tm
->tcpm_fastopen
;
692 write_seqlock_bh(&fastopen_seqlock
);
695 if (cookie
&& cookie
->len
> 0)
696 tfom
->cookie
= *cookie
;
699 tfom
->last_syn_loss
= jiffies
;
702 write_sequnlock_bh(&fastopen_seqlock
);
707 static struct genl_family tcp_metrics_nl_family
= {
708 .id
= GENL_ID_GENERATE
,
710 .name
= TCP_METRICS_GENL_NAME
,
711 .version
= TCP_METRICS_GENL_VERSION
,
712 .maxattr
= TCP_METRICS_ATTR_MAX
,
716 static struct nla_policy tcp_metrics_nl_policy
[TCP_METRICS_ATTR_MAX
+ 1] = {
717 [TCP_METRICS_ATTR_ADDR_IPV4
] = { .type
= NLA_U32
, },
718 [TCP_METRICS_ATTR_ADDR_IPV6
] = { .type
= NLA_BINARY
,
719 .len
= sizeof(struct in6_addr
), },
720 /* Following attributes are not received for GET/DEL,
721 * we keep them for reference
724 [TCP_METRICS_ATTR_AGE
] = { .type
= NLA_MSECS
, },
725 [TCP_METRICS_ATTR_TW_TSVAL
] = { .type
= NLA_U32
, },
726 [TCP_METRICS_ATTR_TW_TS_STAMP
] = { .type
= NLA_S32
, },
727 [TCP_METRICS_ATTR_VALS
] = { .type
= NLA_NESTED
, },
728 [TCP_METRICS_ATTR_FOPEN_MSS
] = { .type
= NLA_U16
, },
729 [TCP_METRICS_ATTR_FOPEN_SYN_DROPS
] = { .type
= NLA_U16
, },
730 [TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS
] = { .type
= NLA_MSECS
, },
731 [TCP_METRICS_ATTR_FOPEN_COOKIE
] = { .type
= NLA_BINARY
,
732 .len
= TCP_FASTOPEN_COOKIE_MAX
, },
736 /* Add attributes, caller cancels its header on failure */
737 static int tcp_metrics_fill_info(struct sk_buff
*msg
,
738 struct tcp_metrics_block
*tm
)
743 switch (tm
->tcpm_daddr
.family
) {
745 if (nla_put_be32(msg
, TCP_METRICS_ATTR_ADDR_IPV4
,
746 tm
->tcpm_daddr
.addr
.a4
) < 0)
747 goto nla_put_failure
;
748 if (nla_put_be32(msg
, TCP_METRICS_ATTR_SADDR_IPV4
,
749 tm
->tcpm_saddr
.addr
.a4
) < 0)
750 goto nla_put_failure
;
753 if (nla_put(msg
, TCP_METRICS_ATTR_ADDR_IPV6
, 16,
754 tm
->tcpm_daddr
.addr
.a6
) < 0)
755 goto nla_put_failure
;
756 if (nla_put(msg
, TCP_METRICS_ATTR_SADDR_IPV6
, 16,
757 tm
->tcpm_saddr
.addr
.a6
) < 0)
758 goto nla_put_failure
;
761 return -EAFNOSUPPORT
;
764 if (nla_put_msecs(msg
, TCP_METRICS_ATTR_AGE
,
765 jiffies
- tm
->tcpm_stamp
) < 0)
766 goto nla_put_failure
;
767 if (tm
->tcpm_ts_stamp
) {
768 if (nla_put_s32(msg
, TCP_METRICS_ATTR_TW_TS_STAMP
,
769 (s32
) (get_seconds() - tm
->tcpm_ts_stamp
)) < 0)
770 goto nla_put_failure
;
771 if (nla_put_u32(msg
, TCP_METRICS_ATTR_TW_TSVAL
,
773 goto nla_put_failure
;
779 nest
= nla_nest_start(msg
, TCP_METRICS_ATTR_VALS
);
781 goto nla_put_failure
;
782 for (i
= 0; i
< TCP_METRIC_MAX
+ 1; i
++) {
783 if (!tm
->tcpm_vals
[i
])
785 if (nla_put_u32(msg
, i
+ 1, tm
->tcpm_vals
[i
]) < 0)
786 goto nla_put_failure
;
790 nla_nest_end(msg
, nest
);
792 nla_nest_cancel(msg
, nest
);
796 struct tcp_fastopen_metrics tfom_copy
[1], *tfom
;
800 seq
= read_seqbegin(&fastopen_seqlock
);
801 tfom_copy
[0] = tm
->tcpm_fastopen
;
802 } while (read_seqretry(&fastopen_seqlock
, seq
));
806 nla_put_u16(msg
, TCP_METRICS_ATTR_FOPEN_MSS
,
808 goto nla_put_failure
;
809 if (tfom
->syn_loss
&&
810 (nla_put_u16(msg
, TCP_METRICS_ATTR_FOPEN_SYN_DROPS
,
811 tfom
->syn_loss
) < 0 ||
812 nla_put_msecs(msg
, TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS
,
813 jiffies
- tfom
->last_syn_loss
) < 0))
814 goto nla_put_failure
;
815 if (tfom
->cookie
.len
> 0 &&
816 nla_put(msg
, TCP_METRICS_ATTR_FOPEN_COOKIE
,
817 tfom
->cookie
.len
, tfom
->cookie
.val
) < 0)
818 goto nla_put_failure
;
827 static int tcp_metrics_dump_info(struct sk_buff
*skb
,
828 struct netlink_callback
*cb
,
829 struct tcp_metrics_block
*tm
)
833 hdr
= genlmsg_put(skb
, NETLINK_CB(cb
->skb
).portid
, cb
->nlh
->nlmsg_seq
,
834 &tcp_metrics_nl_family
, NLM_F_MULTI
,
835 TCP_METRICS_CMD_GET
);
839 if (tcp_metrics_fill_info(skb
, tm
) < 0)
840 goto nla_put_failure
;
842 return genlmsg_end(skb
, hdr
);
845 genlmsg_cancel(skb
, hdr
);
849 static int tcp_metrics_nl_dump(struct sk_buff
*skb
,
850 struct netlink_callback
*cb
)
852 struct net
*net
= sock_net(skb
->sk
);
853 unsigned int max_rows
= 1U << net
->ipv4
.tcp_metrics_hash_log
;
854 unsigned int row
, s_row
= cb
->args
[0];
855 int s_col
= cb
->args
[1], col
= s_col
;
857 for (row
= s_row
; row
< max_rows
; row
++, s_col
= 0) {
858 struct tcp_metrics_block
*tm
;
859 struct tcpm_hash_bucket
*hb
= net
->ipv4
.tcp_metrics_hash
+ row
;
862 for (col
= 0, tm
= rcu_dereference(hb
->chain
); tm
;
863 tm
= rcu_dereference(tm
->tcpm_next
), col
++) {
866 if (tcp_metrics_dump_info(skb
, cb
, tm
) < 0) {
880 static int __parse_nl_addr(struct genl_info
*info
, struct inetpeer_addr
*addr
,
881 unsigned int *hash
, int optional
, int v4
, int v6
)
887 addr
->family
= AF_INET
;
888 addr
->addr
.a4
= nla_get_be32(a
);
890 *hash
= (__force
unsigned int) addr
->addr
.a4
;
895 if (nla_len(a
) != sizeof(struct in6_addr
))
897 addr
->family
= AF_INET6
;
898 memcpy(addr
->addr
.a6
, nla_data(a
), sizeof(addr
->addr
.a6
));
900 *hash
= ipv6_addr_hash((struct in6_addr
*) addr
->addr
.a6
);
903 return optional
? 1 : -EAFNOSUPPORT
;
906 static int parse_nl_addr(struct genl_info
*info
, struct inetpeer_addr
*addr
,
907 unsigned int *hash
, int optional
)
909 return __parse_nl_addr(info
, addr
, hash
, optional
,
910 TCP_METRICS_ATTR_ADDR_IPV4
,
911 TCP_METRICS_ATTR_ADDR_IPV6
);
914 static int parse_nl_saddr(struct genl_info
*info
, struct inetpeer_addr
*addr
)
916 return __parse_nl_addr(info
, addr
, NULL
, 0,
917 TCP_METRICS_ATTR_SADDR_IPV4
,
918 TCP_METRICS_ATTR_SADDR_IPV6
);
921 static int tcp_metrics_nl_cmd_get(struct sk_buff
*skb
, struct genl_info
*info
)
923 struct tcp_metrics_block
*tm
;
924 struct inetpeer_addr saddr
, daddr
;
927 struct net
*net
= genl_info_net(info
);
932 ret
= parse_nl_addr(info
, &daddr
, &hash
, 0);
936 ret
= parse_nl_saddr(info
, &saddr
);
940 msg
= nlmsg_new(NLMSG_DEFAULT_SIZE
, GFP_KERNEL
);
944 reply
= genlmsg_put_reply(msg
, info
, &tcp_metrics_nl_family
, 0,
947 goto nla_put_failure
;
949 hash
= hash_32(hash
, net
->ipv4
.tcp_metrics_hash_log
);
952 for (tm
= rcu_dereference(net
->ipv4
.tcp_metrics_hash
[hash
].chain
); tm
;
953 tm
= rcu_dereference(tm
->tcpm_next
)) {
954 if (addr_same(&tm
->tcpm_daddr
, &daddr
) &&
955 (!src
|| addr_same(&tm
->tcpm_saddr
, &saddr
))) {
956 ret
= tcp_metrics_fill_info(msg
, tm
);
964 genlmsg_end(msg
, reply
);
965 return genlmsg_reply(msg
, info
);
975 #define deref_locked_genl(p) \
976 rcu_dereference_protected(p, lockdep_genl_is_held() && \
977 lockdep_is_held(&tcp_metrics_lock))
979 #define deref_genl(p) rcu_dereference_protected(p, lockdep_genl_is_held())
981 static int tcp_metrics_flush_all(struct net
*net
)
983 unsigned int max_rows
= 1U << net
->ipv4
.tcp_metrics_hash_log
;
984 struct tcpm_hash_bucket
*hb
= net
->ipv4
.tcp_metrics_hash
;
985 struct tcp_metrics_block
*tm
;
988 for (row
= 0; row
< max_rows
; row
++, hb
++) {
989 spin_lock_bh(&tcp_metrics_lock
);
990 tm
= deref_locked_genl(hb
->chain
);
993 spin_unlock_bh(&tcp_metrics_lock
);
995 struct tcp_metrics_block
*next
;
997 next
= deref_genl(tm
->tcpm_next
);
998 kfree_rcu(tm
, rcu_head
);
1005 static int tcp_metrics_nl_cmd_del(struct sk_buff
*skb
, struct genl_info
*info
)
1007 struct tcpm_hash_bucket
*hb
;
1008 struct tcp_metrics_block
*tm
, *tmlist
= NULL
;
1009 struct tcp_metrics_block __rcu
**pp
;
1010 struct inetpeer_addr saddr
, daddr
;
1012 struct net
*net
= genl_info_net(info
);
1016 ret
= parse_nl_addr(info
, &daddr
, &hash
, 1);
1020 return tcp_metrics_flush_all(net
);
1021 ret
= parse_nl_saddr(info
, &saddr
);
1025 hash
= hash_32(hash
, net
->ipv4
.tcp_metrics_hash_log
);
1026 hb
= net
->ipv4
.tcp_metrics_hash
+ hash
;
1028 spin_lock_bh(&tcp_metrics_lock
);
1029 for (tm
= deref_locked_genl(*pp
); tm
; tm
= deref_locked_genl(*pp
)) {
1030 if (addr_same(&tm
->tcpm_daddr
, &daddr
) &&
1031 (!src
|| addr_same(&tm
->tcpm_saddr
, &saddr
))) {
1032 *pp
= tm
->tcpm_next
;
1033 tm
->tcpm_next
= tmlist
;
1036 pp
= &tm
->tcpm_next
;
1039 spin_unlock_bh(&tcp_metrics_lock
);
1042 for (tm
= tmlist
; tm
; tm
= tmlist
) {
1043 tmlist
= tm
->tcpm_next
;
1044 kfree_rcu(tm
, rcu_head
);
1049 static const struct genl_ops tcp_metrics_nl_ops
[] = {
1051 .cmd
= TCP_METRICS_CMD_GET
,
1052 .doit
= tcp_metrics_nl_cmd_get
,
1053 .dumpit
= tcp_metrics_nl_dump
,
1054 .policy
= tcp_metrics_nl_policy
,
1055 .flags
= GENL_ADMIN_PERM
,
1058 .cmd
= TCP_METRICS_CMD_DEL
,
1059 .doit
= tcp_metrics_nl_cmd_del
,
1060 .policy
= tcp_metrics_nl_policy
,
1061 .flags
= GENL_ADMIN_PERM
,
1065 static unsigned int tcpmhash_entries
;
1066 static int __init
set_tcpmhash_entries(char *str
)
1073 ret
= kstrtouint(str
, 0, &tcpmhash_entries
);
1079 __setup("tcpmhash_entries=", set_tcpmhash_entries
);
1081 static int __net_init
tcp_net_metrics_init(struct net
*net
)
1086 slots
= tcpmhash_entries
;
1088 if (totalram_pages
>= 128 * 1024)
1094 net
->ipv4
.tcp_metrics_hash_log
= order_base_2(slots
);
1095 size
= sizeof(struct tcpm_hash_bucket
) << net
->ipv4
.tcp_metrics_hash_log
;
1097 net
->ipv4
.tcp_metrics_hash
= kzalloc(size
, GFP_KERNEL
| __GFP_NOWARN
);
1098 if (!net
->ipv4
.tcp_metrics_hash
)
1099 net
->ipv4
.tcp_metrics_hash
= vzalloc(size
);
1101 if (!net
->ipv4
.tcp_metrics_hash
)
1107 static void __net_exit
tcp_net_metrics_exit(struct net
*net
)
1111 for (i
= 0; i
< (1U << net
->ipv4
.tcp_metrics_hash_log
) ; i
++) {
1112 struct tcp_metrics_block
*tm
, *next
;
1114 tm
= rcu_dereference_protected(net
->ipv4
.tcp_metrics_hash
[i
].chain
, 1);
1116 next
= rcu_dereference_protected(tm
->tcpm_next
, 1);
1121 if (is_vmalloc_addr(net
->ipv4
.tcp_metrics_hash
))
1122 vfree(net
->ipv4
.tcp_metrics_hash
);
1124 kfree(net
->ipv4
.tcp_metrics_hash
);
1127 static __net_initdata
struct pernet_operations tcp_net_metrics_ops
= {
1128 .init
= tcp_net_metrics_init
,
1129 .exit
= tcp_net_metrics_exit
,
1132 void __init
tcp_metrics_init(void)
1136 ret
= register_pernet_subsys(&tcp_net_metrics_ops
);
1139 ret
= genl_register_family_with_ops(&tcp_metrics_nl_family
,
1140 tcp_metrics_nl_ops
);
1142 goto cleanup_subsys
;
1146 unregister_pernet_subsys(&tcp_net_metrics_ops
);