Commit | Line | Data |
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51c5d0c4 DM |
1 | #include <linux/rcupdate.h> |
2 | #include <linux/spinlock.h> | |
3 | #include <linux/jiffies.h> | |
ab92bb2f | 4 | #include <linux/module.h> |
4aabd8ef | 5 | #include <linux/cache.h> |
51c5d0c4 DM |
6 | #include <linux/slab.h> |
7 | #include <linux/init.h> | |
4aabd8ef | 8 | #include <linux/tcp.h> |
5815d5e7 | 9 | #include <linux/hash.h> |
d23ff701 | 10 | #include <linux/tcp_metrics.h> |
976a702a | 11 | #include <linux/vmalloc.h> |
4aabd8ef DM |
12 | |
13 | #include <net/inet_connection_sock.h> | |
51c5d0c4 | 14 | #include <net/net_namespace.h> |
ab92bb2f | 15 | #include <net/request_sock.h> |
51c5d0c4 | 16 | #include <net/inetpeer.h> |
4aabd8ef | 17 | #include <net/sock.h> |
51c5d0c4 | 18 | #include <net/ipv6.h> |
4aabd8ef DM |
19 | #include <net/dst.h> |
20 | #include <net/tcp.h> | |
d23ff701 | 21 | #include <net/genetlink.h> |
4aabd8ef DM |
22 | |
23 | int sysctl_tcp_nometrics_save __read_mostly; | |
24 | ||
1fe4c481 YC |
25 | struct tcp_fastopen_metrics { |
26 | u16 mss; | |
aab48743 YC |
27 | u16 syn_loss:10; /* Recurring Fast Open SYN losses */ |
28 | unsigned long last_syn_loss; /* Last Fast Open SYN loss */ | |
1fe4c481 YC |
29 | struct tcp_fastopen_cookie cookie; |
30 | }; | |
31 | ||
51c5d0c4 DM |
32 | struct tcp_metrics_block { |
33 | struct tcp_metrics_block __rcu *tcpm_next; | |
a5443028 | 34 | struct inetpeer_addr tcpm_saddr; |
324fd55a | 35 | struct inetpeer_addr tcpm_daddr; |
51c5d0c4 | 36 | unsigned long tcpm_stamp; |
81166dd6 DM |
37 | u32 tcpm_ts; |
38 | u32 tcpm_ts_stamp; | |
51c5d0c4 | 39 | u32 tcpm_lock; |
d23ff701 | 40 | u32 tcpm_vals[TCP_METRIC_MAX + 1]; |
1fe4c481 | 41 | struct tcp_fastopen_metrics tcpm_fastopen; |
d23ff701 JA |
42 | |
43 | struct rcu_head rcu_head; | |
51c5d0c4 DM |
44 | }; |
45 | ||
46 | static bool tcp_metric_locked(struct tcp_metrics_block *tm, | |
47 | enum tcp_metric_index idx) | |
48 | { | |
49 | return tm->tcpm_lock & (1 << idx); | |
50 | } | |
51 | ||
52 | static u32 tcp_metric_get(struct tcp_metrics_block *tm, | |
53 | enum tcp_metric_index idx) | |
54 | { | |
55 | return tm->tcpm_vals[idx]; | |
56 | } | |
57 | ||
58 | static u32 tcp_metric_get_jiffies(struct tcp_metrics_block *tm, | |
59 | enum tcp_metric_index idx) | |
60 | { | |
61 | return msecs_to_jiffies(tm->tcpm_vals[idx]); | |
62 | } | |
63 | ||
64 | static void tcp_metric_set(struct tcp_metrics_block *tm, | |
65 | enum tcp_metric_index idx, | |
66 | u32 val) | |
67 | { | |
68 | tm->tcpm_vals[idx] = val; | |
69 | } | |
70 | ||
71 | static void tcp_metric_set_msecs(struct tcp_metrics_block *tm, | |
72 | enum tcp_metric_index idx, | |
73 | u32 val) | |
74 | { | |
75 | tm->tcpm_vals[idx] = jiffies_to_msecs(val); | |
76 | } | |
77 | ||
78 | static bool addr_same(const struct inetpeer_addr *a, | |
79 | const struct inetpeer_addr *b) | |
80 | { | |
81 | const struct in6_addr *a6, *b6; | |
82 | ||
83 | if (a->family != b->family) | |
84 | return false; | |
85 | if (a->family == AF_INET) | |
86 | return a->addr.a4 == b->addr.a4; | |
87 | ||
88 | a6 = (const struct in6_addr *) &a->addr.a6[0]; | |
89 | b6 = (const struct in6_addr *) &b->addr.a6[0]; | |
90 | ||
91 | return ipv6_addr_equal(a6, b6); | |
92 | } | |
93 | ||
94 | struct tcpm_hash_bucket { | |
95 | struct tcp_metrics_block __rcu *chain; | |
96 | }; | |
97 | ||
98 | static DEFINE_SPINLOCK(tcp_metrics_lock); | |
99 | ||
efeaa555 ED |
100 | static void tcpm_suck_dst(struct tcp_metrics_block *tm, struct dst_entry *dst, |
101 | bool fastopen_clear) | |
51c5d0c4 DM |
102 | { |
103 | u32 val; | |
104 | ||
9a0a9502 JA |
105 | tm->tcpm_stamp = jiffies; |
106 | ||
51c5d0c4 DM |
107 | val = 0; |
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; | |
118 | tm->tcpm_lock = val; | |
119 | ||
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); | |
81166dd6 DM |
125 | tm->tcpm_ts = 0; |
126 | tm->tcpm_ts_stamp = 0; | |
efeaa555 ED |
127 | if (fastopen_clear) { |
128 | tm->tcpm_fastopen.mss = 0; | |
129 | tm->tcpm_fastopen.syn_loss = 0; | |
130 | tm->tcpm_fastopen.cookie.len = 0; | |
131 | } | |
51c5d0c4 DM |
132 | } |
133 | ||
134 | static struct tcp_metrics_block *tcpm_new(struct dst_entry *dst, | |
a5443028 | 135 | struct inetpeer_addr *saddr, |
324fd55a | 136 | struct inetpeer_addr *daddr, |
51c5d0c4 DM |
137 | unsigned int hash, |
138 | bool reclaim) | |
139 | { | |
140 | struct tcp_metrics_block *tm; | |
141 | struct net *net; | |
142 | ||
143 | spin_lock_bh(&tcp_metrics_lock); | |
144 | net = dev_net(dst->dev); | |
145 | if (unlikely(reclaim)) { | |
146 | struct tcp_metrics_block *oldest; | |
147 | ||
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)) | |
152 | oldest = tm; | |
153 | } | |
154 | tm = oldest; | |
155 | } else { | |
156 | tm = kmalloc(sizeof(*tm), GFP_ATOMIC); | |
157 | if (!tm) | |
158 | goto out_unlock; | |
159 | } | |
a5443028 | 160 | tm->tcpm_saddr = *saddr; |
324fd55a | 161 | tm->tcpm_daddr = *daddr; |
51c5d0c4 | 162 | |
efeaa555 | 163 | tcpm_suck_dst(tm, dst, true); |
51c5d0c4 DM |
164 | |
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); | |
168 | } | |
169 | ||
170 | out_unlock: | |
171 | spin_unlock_bh(&tcp_metrics_lock); | |
172 | return tm; | |
173 | } | |
174 | ||
175 | #define TCP_METRICS_TIMEOUT (60 * 60 * HZ) | |
176 | ||
177 | static void tcpm_check_stamp(struct tcp_metrics_block *tm, struct dst_entry *dst) | |
178 | { | |
179 | if (tm && unlikely(time_after(jiffies, tm->tcpm_stamp + TCP_METRICS_TIMEOUT))) | |
efeaa555 | 180 | tcpm_suck_dst(tm, dst, false); |
51c5d0c4 DM |
181 | } |
182 | ||
183 | #define TCP_METRICS_RECLAIM_DEPTH 5 | |
184 | #define TCP_METRICS_RECLAIM_PTR (struct tcp_metrics_block *) 0x1UL | |
185 | ||
186 | static struct tcp_metrics_block *tcp_get_encode(struct tcp_metrics_block *tm, int depth) | |
187 | { | |
188 | if (tm) | |
189 | return tm; | |
190 | if (depth > TCP_METRICS_RECLAIM_DEPTH) | |
191 | return TCP_METRICS_RECLAIM_PTR; | |
192 | return NULL; | |
193 | } | |
194 | ||
a5443028 CP |
195 | static struct tcp_metrics_block *__tcp_get_metrics(const struct inetpeer_addr *saddr, |
196 | const struct inetpeer_addr *daddr, | |
51c5d0c4 DM |
197 | struct net *net, unsigned int hash) |
198 | { | |
199 | struct tcp_metrics_block *tm; | |
200 | int depth = 0; | |
201 | ||
202 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
203 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
204 | if (addr_same(&tm->tcpm_saddr, saddr) && |
205 | addr_same(&tm->tcpm_daddr, daddr)) | |
51c5d0c4 DM |
206 | break; |
207 | depth++; | |
208 | } | |
209 | return tcp_get_encode(tm, depth); | |
210 | } | |
211 | ||
212 | static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req, | |
213 | struct dst_entry *dst) | |
214 | { | |
215 | struct tcp_metrics_block *tm; | |
a5443028 | 216 | struct inetpeer_addr saddr, daddr; |
51c5d0c4 DM |
217 | unsigned int hash; |
218 | struct net *net; | |
219 | ||
a5443028 | 220 | saddr.family = req->rsk_ops->family; |
324fd55a CP |
221 | daddr.family = req->rsk_ops->family; |
222 | switch (daddr.family) { | |
51c5d0c4 | 223 | case AF_INET: |
a5443028 | 224 | saddr.addr.a4 = inet_rsk(req)->ir_loc_addr; |
324fd55a CP |
225 | daddr.addr.a4 = inet_rsk(req)->ir_rmt_addr; |
226 | hash = (__force unsigned int) daddr.addr.a4; | |
51c5d0c4 | 227 | break; |
634fb979 | 228 | #if IS_ENABLED(CONFIG_IPV6) |
51c5d0c4 | 229 | case AF_INET6: |
a5443028 | 230 | *(struct in6_addr *)saddr.addr.a6 = inet_rsk(req)->ir_v6_loc_addr; |
324fd55a | 231 | *(struct in6_addr *)daddr.addr.a6 = inet_rsk(req)->ir_v6_rmt_addr; |
634fb979 | 232 | hash = ipv6_addr_hash(&inet_rsk(req)->ir_v6_rmt_addr); |
51c5d0c4 | 233 | break; |
634fb979 | 234 | #endif |
51c5d0c4 DM |
235 | default: |
236 | return NULL; | |
237 | } | |
238 | ||
51c5d0c4 | 239 | net = dev_net(dst->dev); |
5815d5e7 | 240 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
51c5d0c4 DM |
241 | |
242 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
243 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
244 | if (addr_same(&tm->tcpm_saddr, &saddr) && |
245 | addr_same(&tm->tcpm_daddr, &daddr)) | |
51c5d0c4 DM |
246 | break; |
247 | } | |
248 | tcpm_check_stamp(tm, dst); | |
249 | return tm; | |
250 | } | |
251 | ||
81166dd6 DM |
252 | static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock *tw) |
253 | { | |
81166dd6 | 254 | struct tcp_metrics_block *tm; |
a5443028 | 255 | struct inetpeer_addr saddr, daddr; |
81166dd6 DM |
256 | unsigned int hash; |
257 | struct net *net; | |
258 | ||
a5443028 | 259 | saddr.family = tw->tw_family; |
324fd55a CP |
260 | daddr.family = tw->tw_family; |
261 | switch (daddr.family) { | |
81166dd6 | 262 | case AF_INET: |
a5443028 | 263 | saddr.addr.a4 = tw->tw_rcv_saddr; |
324fd55a CP |
264 | daddr.addr.a4 = tw->tw_daddr; |
265 | hash = (__force unsigned int) daddr.addr.a4; | |
81166dd6 | 266 | break; |
c2bb06db | 267 | #if IS_ENABLED(CONFIG_IPV6) |
81166dd6 | 268 | case AF_INET6: |
a5443028 | 269 | *(struct in6_addr *)saddr.addr.a6 = tw->tw_v6_rcv_saddr; |
324fd55a | 270 | *(struct in6_addr *)daddr.addr.a6 = tw->tw_v6_daddr; |
efe4208f | 271 | hash = ipv6_addr_hash(&tw->tw_v6_daddr); |
81166dd6 | 272 | break; |
c2bb06db | 273 | #endif |
81166dd6 DM |
274 | default: |
275 | return NULL; | |
276 | } | |
277 | ||
81166dd6 | 278 | net = twsk_net(tw); |
5815d5e7 | 279 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
81166dd6 DM |
280 | |
281 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
282 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
283 | if (addr_same(&tm->tcpm_saddr, &saddr) && |
284 | addr_same(&tm->tcpm_daddr, &daddr)) | |
81166dd6 DM |
285 | break; |
286 | } | |
287 | return tm; | |
288 | } | |
289 | ||
51c5d0c4 DM |
290 | static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk, |
291 | struct dst_entry *dst, | |
292 | bool create) | |
293 | { | |
294 | struct tcp_metrics_block *tm; | |
a5443028 | 295 | struct inetpeer_addr saddr, daddr; |
51c5d0c4 DM |
296 | unsigned int hash; |
297 | struct net *net; | |
298 | bool reclaim; | |
299 | ||
a5443028 | 300 | saddr.family = sk->sk_family; |
324fd55a CP |
301 | daddr.family = sk->sk_family; |
302 | switch (daddr.family) { | |
51c5d0c4 | 303 | case AF_INET: |
a5443028 | 304 | saddr.addr.a4 = inet_sk(sk)->inet_saddr; |
324fd55a CP |
305 | daddr.addr.a4 = inet_sk(sk)->inet_daddr; |
306 | hash = (__force unsigned int) daddr.addr.a4; | |
51c5d0c4 | 307 | break; |
c2bb06db | 308 | #if IS_ENABLED(CONFIG_IPV6) |
51c5d0c4 | 309 | case AF_INET6: |
a5443028 | 310 | *(struct in6_addr *)saddr.addr.a6 = sk->sk_v6_rcv_saddr; |
324fd55a | 311 | *(struct in6_addr *)daddr.addr.a6 = sk->sk_v6_daddr; |
efe4208f | 312 | hash = ipv6_addr_hash(&sk->sk_v6_daddr); |
51c5d0c4 | 313 | break; |
c2bb06db | 314 | #endif |
51c5d0c4 DM |
315 | default: |
316 | return NULL; | |
317 | } | |
318 | ||
51c5d0c4 | 319 | net = dev_net(dst->dev); |
5815d5e7 | 320 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
51c5d0c4 | 321 | |
a5443028 | 322 | tm = __tcp_get_metrics(&saddr, &daddr, net, hash); |
51c5d0c4 DM |
323 | reclaim = false; |
324 | if (tm == TCP_METRICS_RECLAIM_PTR) { | |
325 | reclaim = true; | |
326 | tm = NULL; | |
327 | } | |
328 | if (!tm && create) | |
a5443028 | 329 | tm = tcpm_new(dst, &saddr, &daddr, hash, reclaim); |
51c5d0c4 DM |
330 | else |
331 | tcpm_check_stamp(tm, dst); | |
332 | ||
333 | return tm; | |
334 | } | |
335 | ||
4aabd8ef DM |
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. | |
339 | */ | |
340 | void tcp_update_metrics(struct sock *sk) | |
341 | { | |
51c5d0c4 | 342 | const struct inet_connection_sock *icsk = inet_csk(sk); |
4aabd8ef | 343 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
344 | struct tcp_sock *tp = tcp_sk(sk); |
345 | struct tcp_metrics_block *tm; | |
346 | unsigned long rtt; | |
347 | u32 val; | |
348 | int m; | |
4aabd8ef | 349 | |
51c5d0c4 | 350 | if (sysctl_tcp_nometrics_save || !dst) |
4aabd8ef DM |
351 | return; |
352 | ||
51c5d0c4 | 353 | if (dst->flags & DST_HOST) |
4aabd8ef DM |
354 | dst_confirm(dst); |
355 | ||
51c5d0c4 DM |
356 | rcu_read_lock(); |
357 | if (icsk->icsk_backoff || !tp->srtt) { | |
358 | /* This session failed to estimate rtt. Why? | |
359 | * Probably, no packets returned in time. Reset our | |
360 | * results. | |
361 | */ | |
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); | |
365 | goto out_unlock; | |
366 | } else | |
367 | tm = tcp_get_metrics(sk, dst, true); | |
4aabd8ef | 368 | |
51c5d0c4 DM |
369 | if (!tm) |
370 | goto out_unlock; | |
4aabd8ef | 371 | |
51c5d0c4 DM |
372 | rtt = tcp_metric_get_jiffies(tm, TCP_METRIC_RTT); |
373 | m = rtt - tp->srtt; | |
4aabd8ef | 374 | |
51c5d0c4 DM |
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. | |
378 | */ | |
379 | if (!tcp_metric_locked(tm, TCP_METRIC_RTT)) { | |
380 | if (m <= 0) | |
381 | rtt = tp->srtt; | |
382 | else | |
383 | rtt -= (m >> 3); | |
384 | tcp_metric_set_msecs(tm, TCP_METRIC_RTT, rtt); | |
385 | } | |
4aabd8ef | 386 | |
51c5d0c4 DM |
387 | if (!tcp_metric_locked(tm, TCP_METRIC_RTTVAR)) { |
388 | unsigned long var; | |
4aabd8ef | 389 | |
51c5d0c4 DM |
390 | if (m < 0) |
391 | m = -m; | |
4aabd8ef | 392 | |
51c5d0c4 DM |
393 | /* Scale deviation to rttvar fixed point */ |
394 | m >>= 1; | |
395 | if (m < tp->mdev) | |
396 | m = tp->mdev; | |
4aabd8ef | 397 | |
51c5d0c4 DM |
398 | var = tcp_metric_get_jiffies(tm, TCP_METRIC_RTTVAR); |
399 | if (m >= var) | |
400 | var = m; | |
401 | else | |
402 | var -= (var - m) >> 2; | |
4aabd8ef | 403 | |
51c5d0c4 DM |
404 | tcp_metric_set_msecs(tm, TCP_METRIC_RTTVAR, var); |
405 | } | |
406 | ||
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, | |
413 | tp->snd_cwnd >> 1); | |
414 | } | |
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, | |
419 | tp->snd_cwnd); | |
420 | } | |
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); | |
2100844c | 429 | tcp_metric_set(tm, TCP_METRIC_CWND, (val + tp->snd_cwnd) >> 1); |
51c5d0c4 DM |
430 | } |
431 | } else { | |
432 | /* Else slow start did not finish, cwnd is non-sense, | |
433 | * ssthresh may be also invalid. | |
434 | */ | |
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); | |
439 | } | |
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, | |
444 | tp->snd_ssthresh); | |
445 | } | |
446 | if (!tcp_metric_locked(tm, TCP_METRIC_REORDERING)) { | |
447 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); | |
448 | if (val < tp->reordering && | |
4aabd8ef | 449 | tp->reordering != sysctl_tcp_reordering) |
51c5d0c4 DM |
450 | tcp_metric_set(tm, TCP_METRIC_REORDERING, |
451 | tp->reordering); | |
4aabd8ef DM |
452 | } |
453 | } | |
51c5d0c4 DM |
454 | tm->tcpm_stamp = jiffies; |
455 | out_unlock: | |
456 | rcu_read_unlock(); | |
4aabd8ef DM |
457 | } |
458 | ||
459 | /* Initialize metrics on socket. */ | |
460 | ||
461 | void tcp_init_metrics(struct sock *sk) | |
462 | { | |
4aabd8ef | 463 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
464 | struct tcp_sock *tp = tcp_sk(sk); |
465 | struct tcp_metrics_block *tm; | |
1b7fdd2a | 466 | u32 val, crtt = 0; /* cached RTT scaled by 8 */ |
4aabd8ef DM |
467 | |
468 | if (dst == NULL) | |
469 | goto reset; | |
470 | ||
471 | dst_confirm(dst); | |
472 | ||
51c5d0c4 DM |
473 | rcu_read_lock(); |
474 | tm = tcp_get_metrics(sk, dst, true); | |
475 | if (!tm) { | |
476 | rcu_read_unlock(); | |
477 | goto reset; | |
478 | } | |
479 | ||
480 | if (tcp_metric_locked(tm, TCP_METRIC_CWND)) | |
481 | tp->snd_cwnd_clamp = tcp_metric_get(tm, TCP_METRIC_CWND); | |
482 | ||
483 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
484 | if (val) { | |
485 | tp->snd_ssthresh = val; | |
4aabd8ef DM |
486 | if (tp->snd_ssthresh > tp->snd_cwnd_clamp) |
487 | tp->snd_ssthresh = tp->snd_cwnd_clamp; | |
488 | } else { | |
489 | /* ssthresh may have been reduced unnecessarily during. | |
490 | * 3WHS. Restore it back to its initial default. | |
491 | */ | |
492 | tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; | |
493 | } | |
51c5d0c4 DM |
494 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); |
495 | if (val && tp->reordering != val) { | |
4aabd8ef DM |
496 | tcp_disable_fack(tp); |
497 | tcp_disable_early_retrans(tp); | |
51c5d0c4 | 498 | tp->reordering = val; |
4aabd8ef DM |
499 | } |
500 | ||
1b7fdd2a | 501 | crtt = tcp_metric_get_jiffies(tm, TCP_METRIC_RTT); |
51c5d0c4 | 502 | rcu_read_unlock(); |
4aabd8ef | 503 | reset: |
52f20e65 YC |
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. | |
511 | * | |
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. | |
514 | * | |
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. | |
523 | */ | |
1b7fdd2a | 524 | if (crtt > tp->srtt) { |
269aa759 NC |
525 | /* Set RTO like tcp_rtt_estimator(), but from cached RTT. */ |
526 | crtt >>= 3; | |
527 | inet_csk(sk)->icsk_rto = crtt + max(2 * crtt, tcp_rto_min(sk)); | |
1b7fdd2a | 528 | } else if (tp->srtt == 0) { |
4aabd8ef DM |
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 | |
533 | * retransmission. | |
534 | */ | |
535 | tp->mdev = tp->mdev_max = tp->rttvar = TCP_TIMEOUT_FALLBACK; | |
536 | inet_csk(sk)->icsk_rto = TCP_TIMEOUT_FALLBACK; | |
537 | } | |
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. | |
542 | */ | |
543 | if (tp->total_retrans > 1) | |
544 | tp->snd_cwnd = 1; | |
545 | else | |
546 | tp->snd_cwnd = tcp_init_cwnd(tp, dst); | |
547 | tp->snd_cwnd_stamp = tcp_time_stamp; | |
548 | } | |
ab92bb2f | 549 | |
81166dd6 | 550 | bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, bool paws_check) |
ab92bb2f | 551 | { |
51c5d0c4 DM |
552 | struct tcp_metrics_block *tm; |
553 | bool ret; | |
554 | ||
ab92bb2f DM |
555 | if (!dst) |
556 | return false; | |
51c5d0c4 DM |
557 | |
558 | rcu_read_lock(); | |
559 | tm = __tcp_get_metrics_req(req, dst); | |
81166dd6 DM |
560 | if (paws_check) { |
561 | if (tm && | |
562 | (u32)get_seconds() - tm->tcpm_ts_stamp < TCP_PAWS_MSL && | |
563 | (s32)(tm->tcpm_ts - req->ts_recent) > TCP_PAWS_WINDOW) | |
564 | ret = false; | |
565 | else | |
566 | ret = true; | |
567 | } else { | |
568 | if (tm && tcp_metric_get(tm, TCP_METRIC_RTT) && tm->tcpm_ts_stamp) | |
569 | ret = true; | |
570 | else | |
571 | ret = false; | |
572 | } | |
51c5d0c4 DM |
573 | rcu_read_unlock(); |
574 | ||
575 | return ret; | |
ab92bb2f DM |
576 | } |
577 | EXPORT_SYMBOL_GPL(tcp_peer_is_proven); | |
51c5d0c4 | 578 | |
81166dd6 DM |
579 | void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst) |
580 | { | |
581 | struct tcp_metrics_block *tm; | |
582 | ||
583 | rcu_read_lock(); | |
584 | tm = tcp_get_metrics(sk, dst, true); | |
585 | if (tm) { | |
586 | struct tcp_sock *tp = tcp_sk(sk); | |
587 | ||
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; | |
591 | } | |
592 | } | |
593 | rcu_read_unlock(); | |
594 | } | |
595 | EXPORT_SYMBOL_GPL(tcp_fetch_timewait_stamp); | |
596 | ||
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. | |
601 | */ | |
602 | bool tcp_remember_stamp(struct sock *sk) | |
603 | { | |
604 | struct dst_entry *dst = __sk_dst_get(sk); | |
605 | bool ret = false; | |
606 | ||
607 | if (dst) { | |
608 | struct tcp_metrics_block *tm; | |
609 | ||
610 | rcu_read_lock(); | |
611 | tm = tcp_get_metrics(sk, dst, true); | |
612 | if (tm) { | |
613 | struct tcp_sock *tp = tcp_sk(sk); | |
614 | ||
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; | |
620 | } | |
621 | ret = true; | |
622 | } | |
623 | rcu_read_unlock(); | |
624 | } | |
625 | return ret; | |
626 | } | |
627 | ||
628 | bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw) | |
629 | { | |
630 | struct tcp_metrics_block *tm; | |
631 | bool ret = false; | |
632 | ||
633 | rcu_read_lock(); | |
634 | tm = __tcp_get_metrics_tw(tw); | |
9a0a9502 | 635 | if (tm) { |
81166dd6 DM |
636 | const struct tcp_timewait_sock *tcptw; |
637 | struct sock *sk = (struct sock *) tw; | |
638 | ||
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; | |
645 | } | |
646 | ret = true; | |
647 | } | |
648 | rcu_read_unlock(); | |
649 | ||
650 | return ret; | |
651 | } | |
652 | ||
1fe4c481 YC |
653 | static DEFINE_SEQLOCK(fastopen_seqlock); |
654 | ||
655 | void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, | |
aab48743 YC |
656 | struct tcp_fastopen_cookie *cookie, |
657 | int *syn_loss, unsigned long *last_syn_loss) | |
1fe4c481 YC |
658 | { |
659 | struct tcp_metrics_block *tm; | |
660 | ||
661 | rcu_read_lock(); | |
662 | tm = tcp_get_metrics(sk, __sk_dst_get(sk), false); | |
663 | if (tm) { | |
664 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
665 | unsigned int seq; | |
666 | ||
667 | do { | |
668 | seq = read_seqbegin(&fastopen_seqlock); | |
669 | if (tfom->mss) | |
670 | *mss = tfom->mss; | |
671 | *cookie = tfom->cookie; | |
aab48743 YC |
672 | *syn_loss = tfom->syn_loss; |
673 | *last_syn_loss = *syn_loss ? tfom->last_syn_loss : 0; | |
1fe4c481 YC |
674 | } while (read_seqretry(&fastopen_seqlock, seq)); |
675 | } | |
676 | rcu_read_unlock(); | |
677 | } | |
678 | ||
1fe4c481 | 679 | void tcp_fastopen_cache_set(struct sock *sk, u16 mss, |
aab48743 | 680 | struct tcp_fastopen_cookie *cookie, bool syn_lost) |
1fe4c481 | 681 | { |
dccf76ca | 682 | struct dst_entry *dst = __sk_dst_get(sk); |
1fe4c481 YC |
683 | struct tcp_metrics_block *tm; |
684 | ||
dccf76ca ED |
685 | if (!dst) |
686 | return; | |
1fe4c481 | 687 | rcu_read_lock(); |
dccf76ca | 688 | tm = tcp_get_metrics(sk, dst, true); |
1fe4c481 YC |
689 | if (tm) { |
690 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
691 | ||
692 | write_seqlock_bh(&fastopen_seqlock); | |
c968601d YC |
693 | if (mss) |
694 | tfom->mss = mss; | |
695 | if (cookie && cookie->len > 0) | |
1fe4c481 | 696 | tfom->cookie = *cookie; |
aab48743 YC |
697 | if (syn_lost) { |
698 | ++tfom->syn_loss; | |
699 | tfom->last_syn_loss = jiffies; | |
700 | } else | |
701 | tfom->syn_loss = 0; | |
1fe4c481 YC |
702 | write_sequnlock_bh(&fastopen_seqlock); |
703 | } | |
704 | rcu_read_unlock(); | |
705 | } | |
706 | ||
d23ff701 JA |
707 | static struct genl_family tcp_metrics_nl_family = { |
708 | .id = GENL_ID_GENERATE, | |
709 | .hdrsize = 0, | |
710 | .name = TCP_METRICS_GENL_NAME, | |
711 | .version = TCP_METRICS_GENL_VERSION, | |
712 | .maxattr = TCP_METRICS_ATTR_MAX, | |
713 | .netnsok = true, | |
714 | }; | |
715 | ||
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 | |
722 | */ | |
723 | #if 0 | |
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, }, | |
733 | #endif | |
734 | }; | |
735 | ||
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) | |
739 | { | |
740 | struct nlattr *nest; | |
741 | int i; | |
742 | ||
324fd55a | 743 | switch (tm->tcpm_daddr.family) { |
d23ff701 JA |
744 | case AF_INET: |
745 | if (nla_put_be32(msg, TCP_METRICS_ATTR_ADDR_IPV4, | |
324fd55a | 746 | tm->tcpm_daddr.addr.a4) < 0) |
d23ff701 | 747 | goto nla_put_failure; |
8a59359c CP |
748 | if (nla_put_be32(msg, TCP_METRICS_ATTR_SADDR_IPV4, |
749 | tm->tcpm_saddr.addr.a4) < 0) | |
750 | goto nla_put_failure; | |
d23ff701 JA |
751 | break; |
752 | case AF_INET6: | |
753 | if (nla_put(msg, TCP_METRICS_ATTR_ADDR_IPV6, 16, | |
324fd55a | 754 | tm->tcpm_daddr.addr.a6) < 0) |
d23ff701 | 755 | goto nla_put_failure; |
8a59359c CP |
756 | if (nla_put(msg, TCP_METRICS_ATTR_SADDR_IPV6, 16, |
757 | tm->tcpm_saddr.addr.a6) < 0) | |
758 | goto nla_put_failure; | |
d23ff701 JA |
759 | break; |
760 | default: | |
761 | return -EAFNOSUPPORT; | |
762 | } | |
763 | ||
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, | |
772 | tm->tcpm_ts) < 0) | |
773 | goto nla_put_failure; | |
774 | } | |
775 | ||
776 | { | |
777 | int n = 0; | |
778 | ||
779 | nest = nla_nest_start(msg, TCP_METRICS_ATTR_VALS); | |
780 | if (!nest) | |
781 | goto nla_put_failure; | |
782 | for (i = 0; i < TCP_METRIC_MAX + 1; i++) { | |
783 | if (!tm->tcpm_vals[i]) | |
784 | continue; | |
785 | if (nla_put_u32(msg, i + 1, tm->tcpm_vals[i]) < 0) | |
786 | goto nla_put_failure; | |
787 | n++; | |
788 | } | |
789 | if (n) | |
790 | nla_nest_end(msg, nest); | |
791 | else | |
792 | nla_nest_cancel(msg, nest); | |
793 | } | |
794 | ||
795 | { | |
796 | struct tcp_fastopen_metrics tfom_copy[1], *tfom; | |
797 | unsigned int seq; | |
798 | ||
799 | do { | |
800 | seq = read_seqbegin(&fastopen_seqlock); | |
801 | tfom_copy[0] = tm->tcpm_fastopen; | |
802 | } while (read_seqretry(&fastopen_seqlock, seq)); | |
803 | ||
804 | tfom = tfom_copy; | |
805 | if (tfom->mss && | |
806 | nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_MSS, | |
807 | tfom->mss) < 0) | |
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; | |
819 | } | |
820 | ||
821 | return 0; | |
822 | ||
823 | nla_put_failure: | |
824 | return -EMSGSIZE; | |
825 | } | |
826 | ||
827 | static int tcp_metrics_dump_info(struct sk_buff *skb, | |
828 | struct netlink_callback *cb, | |
829 | struct tcp_metrics_block *tm) | |
830 | { | |
831 | void *hdr; | |
832 | ||
15e47304 | 833 | hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, |
d23ff701 JA |
834 | &tcp_metrics_nl_family, NLM_F_MULTI, |
835 | TCP_METRICS_CMD_GET); | |
836 | if (!hdr) | |
837 | return -EMSGSIZE; | |
838 | ||
839 | if (tcp_metrics_fill_info(skb, tm) < 0) | |
840 | goto nla_put_failure; | |
841 | ||
842 | return genlmsg_end(skb, hdr); | |
843 | ||
844 | nla_put_failure: | |
845 | genlmsg_cancel(skb, hdr); | |
846 | return -EMSGSIZE; | |
847 | } | |
848 | ||
849 | static int tcp_metrics_nl_dump(struct sk_buff *skb, | |
850 | struct netlink_callback *cb) | |
851 | { | |
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; | |
856 | ||
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; | |
860 | ||
861 | rcu_read_lock(); | |
862 | for (col = 0, tm = rcu_dereference(hb->chain); tm; | |
863 | tm = rcu_dereference(tm->tcpm_next), col++) { | |
864 | if (col < s_col) | |
865 | continue; | |
866 | if (tcp_metrics_dump_info(skb, cb, tm) < 0) { | |
867 | rcu_read_unlock(); | |
868 | goto done; | |
869 | } | |
870 | } | |
871 | rcu_read_unlock(); | |
872 | } | |
873 | ||
874 | done: | |
875 | cb->args[0] = row; | |
876 | cb->args[1] = col; | |
877 | return skb->len; | |
878 | } | |
879 | ||
3e7013dd CP |
880 | static int __parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
881 | unsigned int *hash, int optional, int v4, int v6) | |
d23ff701 JA |
882 | { |
883 | struct nlattr *a; | |
884 | ||
3e7013dd | 885 | a = info->attrs[v4]; |
d23ff701 JA |
886 | if (a) { |
887 | addr->family = AF_INET; | |
888 | addr->addr.a4 = nla_get_be32(a); | |
3e7013dd CP |
889 | if (hash) |
890 | *hash = (__force unsigned int) addr->addr.a4; | |
d23ff701 JA |
891 | return 0; |
892 | } | |
3e7013dd | 893 | a = info->attrs[v6]; |
d23ff701 | 894 | if (a) { |
2c42a3fb | 895 | if (nla_len(a) != sizeof(struct in6_addr)) |
d23ff701 JA |
896 | return -EINVAL; |
897 | addr->family = AF_INET6; | |
898 | memcpy(addr->addr.a6, nla_data(a), sizeof(addr->addr.a6)); | |
3e7013dd CP |
899 | if (hash) |
900 | *hash = ipv6_addr_hash((struct in6_addr *) addr->addr.a6); | |
d23ff701 JA |
901 | return 0; |
902 | } | |
903 | return optional ? 1 : -EAFNOSUPPORT; | |
904 | } | |
905 | ||
3e7013dd CP |
906 | static int parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
907 | unsigned int *hash, int optional) | |
908 | { | |
909 | return __parse_nl_addr(info, addr, hash, optional, | |
910 | TCP_METRICS_ATTR_ADDR_IPV4, | |
911 | TCP_METRICS_ATTR_ADDR_IPV6); | |
912 | } | |
913 | ||
914 | static int parse_nl_saddr(struct genl_info *info, struct inetpeer_addr *addr) | |
915 | { | |
916 | return __parse_nl_addr(info, addr, NULL, 0, | |
917 | TCP_METRICS_ATTR_SADDR_IPV4, | |
918 | TCP_METRICS_ATTR_SADDR_IPV6); | |
919 | } | |
920 | ||
d23ff701 JA |
921 | static int tcp_metrics_nl_cmd_get(struct sk_buff *skb, struct genl_info *info) |
922 | { | |
923 | struct tcp_metrics_block *tm; | |
3e7013dd | 924 | struct inetpeer_addr saddr, daddr; |
d23ff701 JA |
925 | unsigned int hash; |
926 | struct sk_buff *msg; | |
927 | struct net *net = genl_info_net(info); | |
928 | void *reply; | |
929 | int ret; | |
3e7013dd | 930 | bool src = true; |
d23ff701 | 931 | |
324fd55a | 932 | ret = parse_nl_addr(info, &daddr, &hash, 0); |
d23ff701 JA |
933 | if (ret < 0) |
934 | return ret; | |
935 | ||
3e7013dd CP |
936 | ret = parse_nl_saddr(info, &saddr); |
937 | if (ret < 0) | |
938 | src = false; | |
939 | ||
d23ff701 JA |
940 | msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
941 | if (!msg) | |
942 | return -ENOMEM; | |
943 | ||
944 | reply = genlmsg_put_reply(msg, info, &tcp_metrics_nl_family, 0, | |
945 | info->genlhdr->cmd); | |
946 | if (!reply) | |
947 | goto nla_put_failure; | |
948 | ||
949 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); | |
950 | ret = -ESRCH; | |
951 | rcu_read_lock(); | |
952 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
953 | tm = rcu_dereference(tm->tcpm_next)) { | |
3e7013dd CP |
954 | if (addr_same(&tm->tcpm_daddr, &daddr) && |
955 | (!src || addr_same(&tm->tcpm_saddr, &saddr))) { | |
d23ff701 JA |
956 | ret = tcp_metrics_fill_info(msg, tm); |
957 | break; | |
958 | } | |
959 | } | |
960 | rcu_read_unlock(); | |
961 | if (ret < 0) | |
962 | goto out_free; | |
963 | ||
964 | genlmsg_end(msg, reply); | |
965 | return genlmsg_reply(msg, info); | |
966 | ||
967 | nla_put_failure: | |
968 | ret = -EMSGSIZE; | |
969 | ||
970 | out_free: | |
971 | nlmsg_free(msg); | |
972 | return ret; | |
973 | } | |
974 | ||
975 | #define deref_locked_genl(p) \ | |
976 | rcu_dereference_protected(p, lockdep_genl_is_held() && \ | |
977 | lockdep_is_held(&tcp_metrics_lock)) | |
978 | ||
979 | #define deref_genl(p) rcu_dereference_protected(p, lockdep_genl_is_held()) | |
980 | ||
981 | static int tcp_metrics_flush_all(struct net *net) | |
982 | { | |
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; | |
986 | unsigned int row; | |
987 | ||
988 | for (row = 0; row < max_rows; row++, hb++) { | |
989 | spin_lock_bh(&tcp_metrics_lock); | |
990 | tm = deref_locked_genl(hb->chain); | |
991 | if (tm) | |
992 | hb->chain = NULL; | |
993 | spin_unlock_bh(&tcp_metrics_lock); | |
994 | while (tm) { | |
995 | struct tcp_metrics_block *next; | |
996 | ||
997 | next = deref_genl(tm->tcpm_next); | |
998 | kfree_rcu(tm, rcu_head); | |
999 | tm = next; | |
1000 | } | |
1001 | } | |
1002 | return 0; | |
1003 | } | |
1004 | ||
1005 | static int tcp_metrics_nl_cmd_del(struct sk_buff *skb, struct genl_info *info) | |
1006 | { | |
1007 | struct tcpm_hash_bucket *hb; | |
bbf852b9 | 1008 | struct tcp_metrics_block *tm, *tmlist = NULL; |
d23ff701 | 1009 | struct tcp_metrics_block __rcu **pp; |
3e7013dd | 1010 | struct inetpeer_addr saddr, daddr; |
d23ff701 JA |
1011 | unsigned int hash; |
1012 | struct net *net = genl_info_net(info); | |
1013 | int ret; | |
3e7013dd | 1014 | bool src = true; |
d23ff701 | 1015 | |
324fd55a | 1016 | ret = parse_nl_addr(info, &daddr, &hash, 1); |
d23ff701 JA |
1017 | if (ret < 0) |
1018 | return ret; | |
1019 | if (ret > 0) | |
1020 | return tcp_metrics_flush_all(net); | |
3e7013dd CP |
1021 | ret = parse_nl_saddr(info, &saddr); |
1022 | if (ret < 0) | |
1023 | src = false; | |
d23ff701 JA |
1024 | |
1025 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); | |
1026 | hb = net->ipv4.tcp_metrics_hash + hash; | |
1027 | pp = &hb->chain; | |
1028 | spin_lock_bh(&tcp_metrics_lock); | |
bbf852b9 | 1029 | for (tm = deref_locked_genl(*pp); tm; tm = deref_locked_genl(*pp)) { |
3e7013dd CP |
1030 | if (addr_same(&tm->tcpm_daddr, &daddr) && |
1031 | (!src || addr_same(&tm->tcpm_saddr, &saddr))) { | |
d23ff701 | 1032 | *pp = tm->tcpm_next; |
bbf852b9 CP |
1033 | tm->tcpm_next = tmlist; |
1034 | tmlist = tm; | |
1035 | } else { | |
1036 | pp = &tm->tcpm_next; | |
d23ff701 JA |
1037 | } |
1038 | } | |
1039 | spin_unlock_bh(&tcp_metrics_lock); | |
bbf852b9 | 1040 | if (!tmlist) |
d23ff701 | 1041 | return -ESRCH; |
bbf852b9 CP |
1042 | for (tm = tmlist; tm; tm = tmlist) { |
1043 | tmlist = tm->tcpm_next; | |
1044 | kfree_rcu(tm, rcu_head); | |
1045 | } | |
d23ff701 JA |
1046 | return 0; |
1047 | } | |
1048 | ||
4534de83 | 1049 | static const struct genl_ops tcp_metrics_nl_ops[] = { |
d23ff701 JA |
1050 | { |
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, | |
1056 | }, | |
1057 | { | |
1058 | .cmd = TCP_METRICS_CMD_DEL, | |
1059 | .doit = tcp_metrics_nl_cmd_del, | |
1060 | .policy = tcp_metrics_nl_policy, | |
1061 | .flags = GENL_ADMIN_PERM, | |
1062 | }, | |
1063 | }; | |
1064 | ||
5815d5e7 | 1065 | static unsigned int tcpmhash_entries; |
51c5d0c4 DM |
1066 | static int __init set_tcpmhash_entries(char *str) |
1067 | { | |
1068 | ssize_t ret; | |
1069 | ||
1070 | if (!str) | |
1071 | return 0; | |
1072 | ||
5815d5e7 | 1073 | ret = kstrtouint(str, 0, &tcpmhash_entries); |
51c5d0c4 DM |
1074 | if (ret) |
1075 | return 0; | |
1076 | ||
1077 | return 1; | |
1078 | } | |
1079 | __setup("tcpmhash_entries=", set_tcpmhash_entries); | |
1080 | ||
1081 | static int __net_init tcp_net_metrics_init(struct net *net) | |
1082 | { | |
5815d5e7 ED |
1083 | size_t size; |
1084 | unsigned int slots; | |
51c5d0c4 DM |
1085 | |
1086 | slots = tcpmhash_entries; | |
1087 | if (!slots) { | |
1088 | if (totalram_pages >= 128 * 1024) | |
1089 | slots = 16 * 1024; | |
1090 | else | |
1091 | slots = 8 * 1024; | |
1092 | } | |
1093 | ||
5815d5e7 ED |
1094 | net->ipv4.tcp_metrics_hash_log = order_base_2(slots); |
1095 | size = sizeof(struct tcpm_hash_bucket) << net->ipv4.tcp_metrics_hash_log; | |
51c5d0c4 | 1096 | |
976a702a ED |
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); | |
1100 | ||
51c5d0c4 DM |
1101 | if (!net->ipv4.tcp_metrics_hash) |
1102 | return -ENOMEM; | |
1103 | ||
51c5d0c4 DM |
1104 | return 0; |
1105 | } | |
1106 | ||
1107 | static void __net_exit tcp_net_metrics_exit(struct net *net) | |
1108 | { | |
36471012 ED |
1109 | unsigned int i; |
1110 | ||
1111 | for (i = 0; i < (1U << net->ipv4.tcp_metrics_hash_log) ; i++) { | |
1112 | struct tcp_metrics_block *tm, *next; | |
1113 | ||
1114 | tm = rcu_dereference_protected(net->ipv4.tcp_metrics_hash[i].chain, 1); | |
1115 | while (tm) { | |
1116 | next = rcu_dereference_protected(tm->tcpm_next, 1); | |
1117 | kfree(tm); | |
1118 | tm = next; | |
1119 | } | |
1120 | } | |
976a702a ED |
1121 | if (is_vmalloc_addr(net->ipv4.tcp_metrics_hash)) |
1122 | vfree(net->ipv4.tcp_metrics_hash); | |
1123 | else | |
1124 | kfree(net->ipv4.tcp_metrics_hash); | |
51c5d0c4 DM |
1125 | } |
1126 | ||
1127 | static __net_initdata struct pernet_operations tcp_net_metrics_ops = { | |
1128 | .init = tcp_net_metrics_init, | |
1129 | .exit = tcp_net_metrics_exit, | |
1130 | }; | |
1131 | ||
1132 | void __init tcp_metrics_init(void) | |
1133 | { | |
d23ff701 JA |
1134 | int ret; |
1135 | ||
1136 | ret = register_pernet_subsys(&tcp_net_metrics_ops); | |
1137 | if (ret < 0) | |
1138 | goto cleanup; | |
1139 | ret = genl_register_family_with_ops(&tcp_metrics_nl_family, | |
c53ed742 | 1140 | tcp_metrics_nl_ops); |
d23ff701 JA |
1141 | if (ret < 0) |
1142 | goto cleanup_subsys; | |
1143 | return; | |
1144 | ||
1145 | cleanup_subsys: | |
1146 | unregister_pernet_subsys(&tcp_net_metrics_ops); | |
1147 | ||
1148 | cleanup: | |
1149 | return; | |
51c5d0c4 | 1150 | } |