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 | ||
41804420 DM |
25 | static struct tcp_metrics_block *__tcp_get_metrics(const struct inetpeer_addr *saddr, |
26 | const struct inetpeer_addr *daddr, | |
77f99ad1 CP |
27 | struct net *net, unsigned int hash); |
28 | ||
1fe4c481 YC |
29 | struct tcp_fastopen_metrics { |
30 | u16 mss; | |
aab48743 YC |
31 | u16 syn_loss:10; /* Recurring Fast Open SYN losses */ |
32 | unsigned long last_syn_loss; /* Last Fast Open SYN loss */ | |
1fe4c481 YC |
33 | struct tcp_fastopen_cookie cookie; |
34 | }; | |
35 | ||
51c5d0c4 DM |
36 | struct tcp_metrics_block { |
37 | struct tcp_metrics_block __rcu *tcpm_next; | |
a5443028 | 38 | struct inetpeer_addr tcpm_saddr; |
324fd55a | 39 | struct inetpeer_addr tcpm_daddr; |
51c5d0c4 | 40 | unsigned long tcpm_stamp; |
81166dd6 DM |
41 | u32 tcpm_ts; |
42 | u32 tcpm_ts_stamp; | |
51c5d0c4 | 43 | u32 tcpm_lock; |
d23ff701 | 44 | u32 tcpm_vals[TCP_METRIC_MAX + 1]; |
1fe4c481 | 45 | struct tcp_fastopen_metrics tcpm_fastopen; |
d23ff701 JA |
46 | |
47 | struct rcu_head rcu_head; | |
51c5d0c4 DM |
48 | }; |
49 | ||
50 | static bool tcp_metric_locked(struct tcp_metrics_block *tm, | |
51 | enum tcp_metric_index idx) | |
52 | { | |
53 | return tm->tcpm_lock & (1 << idx); | |
54 | } | |
55 | ||
56 | static u32 tcp_metric_get(struct tcp_metrics_block *tm, | |
57 | enum tcp_metric_index idx) | |
58 | { | |
59 | return tm->tcpm_vals[idx]; | |
60 | } | |
61 | ||
62 | static u32 tcp_metric_get_jiffies(struct tcp_metrics_block *tm, | |
63 | enum tcp_metric_index idx) | |
64 | { | |
65 | return msecs_to_jiffies(tm->tcpm_vals[idx]); | |
66 | } | |
67 | ||
68 | static void tcp_metric_set(struct tcp_metrics_block *tm, | |
69 | enum tcp_metric_index idx, | |
70 | u32 val) | |
71 | { | |
72 | tm->tcpm_vals[idx] = val; | |
73 | } | |
74 | ||
75 | static void tcp_metric_set_msecs(struct tcp_metrics_block *tm, | |
76 | enum tcp_metric_index idx, | |
77 | u32 val) | |
78 | { | |
79 | tm->tcpm_vals[idx] = jiffies_to_msecs(val); | |
80 | } | |
81 | ||
82 | static bool addr_same(const struct inetpeer_addr *a, | |
83 | const struct inetpeer_addr *b) | |
84 | { | |
85 | const struct in6_addr *a6, *b6; | |
86 | ||
87 | if (a->family != b->family) | |
88 | return false; | |
89 | if (a->family == AF_INET) | |
90 | return a->addr.a4 == b->addr.a4; | |
91 | ||
92 | a6 = (const struct in6_addr *) &a->addr.a6[0]; | |
93 | b6 = (const struct in6_addr *) &b->addr.a6[0]; | |
94 | ||
95 | return ipv6_addr_equal(a6, b6); | |
96 | } | |
97 | ||
98 | struct tcpm_hash_bucket { | |
99 | struct tcp_metrics_block __rcu *chain; | |
100 | }; | |
101 | ||
102 | static DEFINE_SPINLOCK(tcp_metrics_lock); | |
103 | ||
efeaa555 ED |
104 | static void tcpm_suck_dst(struct tcp_metrics_block *tm, struct dst_entry *dst, |
105 | bool fastopen_clear) | |
51c5d0c4 DM |
106 | { |
107 | u32 val; | |
108 | ||
9a0a9502 JA |
109 | tm->tcpm_stamp = jiffies; |
110 | ||
51c5d0c4 DM |
111 | val = 0; |
112 | if (dst_metric_locked(dst, RTAX_RTT)) | |
113 | val |= 1 << TCP_METRIC_RTT; | |
114 | if (dst_metric_locked(dst, RTAX_RTTVAR)) | |
115 | val |= 1 << TCP_METRIC_RTTVAR; | |
116 | if (dst_metric_locked(dst, RTAX_SSTHRESH)) | |
117 | val |= 1 << TCP_METRIC_SSTHRESH; | |
118 | if (dst_metric_locked(dst, RTAX_CWND)) | |
119 | val |= 1 << TCP_METRIC_CWND; | |
120 | if (dst_metric_locked(dst, RTAX_REORDERING)) | |
121 | val |= 1 << TCP_METRIC_REORDERING; | |
122 | tm->tcpm_lock = val; | |
123 | ||
124 | tm->tcpm_vals[TCP_METRIC_RTT] = dst_metric_raw(dst, RTAX_RTT); | |
125 | tm->tcpm_vals[TCP_METRIC_RTTVAR] = dst_metric_raw(dst, RTAX_RTTVAR); | |
126 | tm->tcpm_vals[TCP_METRIC_SSTHRESH] = dst_metric_raw(dst, RTAX_SSTHRESH); | |
127 | tm->tcpm_vals[TCP_METRIC_CWND] = dst_metric_raw(dst, RTAX_CWND); | |
128 | tm->tcpm_vals[TCP_METRIC_REORDERING] = dst_metric_raw(dst, RTAX_REORDERING); | |
81166dd6 DM |
129 | tm->tcpm_ts = 0; |
130 | tm->tcpm_ts_stamp = 0; | |
efeaa555 ED |
131 | if (fastopen_clear) { |
132 | tm->tcpm_fastopen.mss = 0; | |
133 | tm->tcpm_fastopen.syn_loss = 0; | |
134 | tm->tcpm_fastopen.cookie.len = 0; | |
135 | } | |
51c5d0c4 DM |
136 | } |
137 | ||
77f99ad1 CP |
138 | #define TCP_METRICS_TIMEOUT (60 * 60 * HZ) |
139 | ||
140 | static void tcpm_check_stamp(struct tcp_metrics_block *tm, struct dst_entry *dst) | |
141 | { | |
142 | if (tm && unlikely(time_after(jiffies, tm->tcpm_stamp + TCP_METRICS_TIMEOUT))) | |
143 | tcpm_suck_dst(tm, dst, false); | |
144 | } | |
145 | ||
146 | #define TCP_METRICS_RECLAIM_DEPTH 5 | |
147 | #define TCP_METRICS_RECLAIM_PTR (struct tcp_metrics_block *) 0x1UL | |
148 | ||
51c5d0c4 | 149 | static struct tcp_metrics_block *tcpm_new(struct dst_entry *dst, |
a5443028 | 150 | struct inetpeer_addr *saddr, |
324fd55a | 151 | struct inetpeer_addr *daddr, |
77f99ad1 | 152 | unsigned int hash) |
51c5d0c4 DM |
153 | { |
154 | struct tcp_metrics_block *tm; | |
155 | struct net *net; | |
77f99ad1 | 156 | bool reclaim = false; |
51c5d0c4 DM |
157 | |
158 | spin_lock_bh(&tcp_metrics_lock); | |
159 | net = dev_net(dst->dev); | |
77f99ad1 CP |
160 | |
161 | /* While waiting for the spin-lock the cache might have been populated | |
162 | * with this entry and so we have to check again. | |
163 | */ | |
41804420 | 164 | tm = __tcp_get_metrics(saddr, daddr, net, hash); |
77f99ad1 CP |
165 | if (tm == TCP_METRICS_RECLAIM_PTR) { |
166 | reclaim = true; | |
167 | tm = NULL; | |
168 | } | |
169 | if (tm) { | |
170 | tcpm_check_stamp(tm, dst); | |
171 | goto out_unlock; | |
172 | } | |
173 | ||
51c5d0c4 DM |
174 | if (unlikely(reclaim)) { |
175 | struct tcp_metrics_block *oldest; | |
176 | ||
177 | oldest = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); | |
178 | for (tm = rcu_dereference(oldest->tcpm_next); tm; | |
179 | tm = rcu_dereference(tm->tcpm_next)) { | |
180 | if (time_before(tm->tcpm_stamp, oldest->tcpm_stamp)) | |
181 | oldest = tm; | |
182 | } | |
183 | tm = oldest; | |
184 | } else { | |
185 | tm = kmalloc(sizeof(*tm), GFP_ATOMIC); | |
186 | if (!tm) | |
187 | goto out_unlock; | |
188 | } | |
a5443028 | 189 | tm->tcpm_saddr = *saddr; |
324fd55a | 190 | tm->tcpm_daddr = *daddr; |
51c5d0c4 | 191 | |
efeaa555 | 192 | tcpm_suck_dst(tm, dst, true); |
51c5d0c4 DM |
193 | |
194 | if (likely(!reclaim)) { | |
195 | tm->tcpm_next = net->ipv4.tcp_metrics_hash[hash].chain; | |
196 | rcu_assign_pointer(net->ipv4.tcp_metrics_hash[hash].chain, tm); | |
197 | } | |
198 | ||
199 | out_unlock: | |
200 | spin_unlock_bh(&tcp_metrics_lock); | |
201 | return tm; | |
202 | } | |
203 | ||
51c5d0c4 DM |
204 | static struct tcp_metrics_block *tcp_get_encode(struct tcp_metrics_block *tm, int depth) |
205 | { | |
206 | if (tm) | |
207 | return tm; | |
208 | if (depth > TCP_METRICS_RECLAIM_DEPTH) | |
209 | return TCP_METRICS_RECLAIM_PTR; | |
210 | return NULL; | |
211 | } | |
212 | ||
a5443028 CP |
213 | static struct tcp_metrics_block *__tcp_get_metrics(const struct inetpeer_addr *saddr, |
214 | const struct inetpeer_addr *daddr, | |
51c5d0c4 DM |
215 | struct net *net, unsigned int hash) |
216 | { | |
217 | struct tcp_metrics_block *tm; | |
218 | int depth = 0; | |
219 | ||
220 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
221 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
222 | if (addr_same(&tm->tcpm_saddr, saddr) && |
223 | addr_same(&tm->tcpm_daddr, daddr)) | |
51c5d0c4 DM |
224 | break; |
225 | depth++; | |
226 | } | |
227 | return tcp_get_encode(tm, depth); | |
228 | } | |
229 | ||
230 | static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req, | |
231 | struct dst_entry *dst) | |
232 | { | |
233 | struct tcp_metrics_block *tm; | |
a5443028 | 234 | struct inetpeer_addr saddr, daddr; |
51c5d0c4 DM |
235 | unsigned int hash; |
236 | struct net *net; | |
237 | ||
a5443028 | 238 | saddr.family = req->rsk_ops->family; |
324fd55a CP |
239 | daddr.family = req->rsk_ops->family; |
240 | switch (daddr.family) { | |
51c5d0c4 | 241 | case AF_INET: |
a5443028 | 242 | saddr.addr.a4 = inet_rsk(req)->ir_loc_addr; |
324fd55a CP |
243 | daddr.addr.a4 = inet_rsk(req)->ir_rmt_addr; |
244 | hash = (__force unsigned int) daddr.addr.a4; | |
51c5d0c4 | 245 | break; |
634fb979 | 246 | #if IS_ENABLED(CONFIG_IPV6) |
51c5d0c4 | 247 | case AF_INET6: |
a5443028 | 248 | *(struct in6_addr *)saddr.addr.a6 = inet_rsk(req)->ir_v6_loc_addr; |
324fd55a | 249 | *(struct in6_addr *)daddr.addr.a6 = inet_rsk(req)->ir_v6_rmt_addr; |
634fb979 | 250 | hash = ipv6_addr_hash(&inet_rsk(req)->ir_v6_rmt_addr); |
51c5d0c4 | 251 | break; |
634fb979 | 252 | #endif |
51c5d0c4 DM |
253 | default: |
254 | return NULL; | |
255 | } | |
256 | ||
51c5d0c4 | 257 | net = dev_net(dst->dev); |
5815d5e7 | 258 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
51c5d0c4 DM |
259 | |
260 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
261 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
262 | if (addr_same(&tm->tcpm_saddr, &saddr) && |
263 | addr_same(&tm->tcpm_daddr, &daddr)) | |
51c5d0c4 DM |
264 | break; |
265 | } | |
266 | tcpm_check_stamp(tm, dst); | |
267 | return tm; | |
268 | } | |
269 | ||
81166dd6 DM |
270 | static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock *tw) |
271 | { | |
81166dd6 | 272 | struct tcp_metrics_block *tm; |
a5443028 | 273 | struct inetpeer_addr saddr, daddr; |
81166dd6 DM |
274 | unsigned int hash; |
275 | struct net *net; | |
276 | ||
a5443028 | 277 | saddr.family = tw->tw_family; |
324fd55a CP |
278 | daddr.family = tw->tw_family; |
279 | switch (daddr.family) { | |
81166dd6 | 280 | case AF_INET: |
a5443028 | 281 | saddr.addr.a4 = tw->tw_rcv_saddr; |
324fd55a CP |
282 | daddr.addr.a4 = tw->tw_daddr; |
283 | hash = (__force unsigned int) daddr.addr.a4; | |
81166dd6 | 284 | break; |
c2bb06db | 285 | #if IS_ENABLED(CONFIG_IPV6) |
81166dd6 | 286 | case AF_INET6: |
a5443028 | 287 | *(struct in6_addr *)saddr.addr.a6 = tw->tw_v6_rcv_saddr; |
324fd55a | 288 | *(struct in6_addr *)daddr.addr.a6 = tw->tw_v6_daddr; |
efe4208f | 289 | hash = ipv6_addr_hash(&tw->tw_v6_daddr); |
81166dd6 | 290 | break; |
c2bb06db | 291 | #endif |
81166dd6 DM |
292 | default: |
293 | return NULL; | |
294 | } | |
295 | ||
81166dd6 | 296 | net = twsk_net(tw); |
5815d5e7 | 297 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
81166dd6 DM |
298 | |
299 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
300 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
301 | if (addr_same(&tm->tcpm_saddr, &saddr) && |
302 | addr_same(&tm->tcpm_daddr, &daddr)) | |
81166dd6 DM |
303 | break; |
304 | } | |
305 | return tm; | |
306 | } | |
307 | ||
51c5d0c4 DM |
308 | static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk, |
309 | struct dst_entry *dst, | |
310 | bool create) | |
311 | { | |
312 | struct tcp_metrics_block *tm; | |
a5443028 | 313 | struct inetpeer_addr saddr, daddr; |
51c5d0c4 DM |
314 | unsigned int hash; |
315 | struct net *net; | |
51c5d0c4 | 316 | |
a5443028 | 317 | saddr.family = sk->sk_family; |
324fd55a CP |
318 | daddr.family = sk->sk_family; |
319 | switch (daddr.family) { | |
51c5d0c4 | 320 | case AF_INET: |
a5443028 | 321 | saddr.addr.a4 = inet_sk(sk)->inet_saddr; |
324fd55a CP |
322 | daddr.addr.a4 = inet_sk(sk)->inet_daddr; |
323 | hash = (__force unsigned int) daddr.addr.a4; | |
51c5d0c4 | 324 | break; |
c2bb06db | 325 | #if IS_ENABLED(CONFIG_IPV6) |
51c5d0c4 | 326 | case AF_INET6: |
a5443028 | 327 | *(struct in6_addr *)saddr.addr.a6 = sk->sk_v6_rcv_saddr; |
324fd55a | 328 | *(struct in6_addr *)daddr.addr.a6 = sk->sk_v6_daddr; |
efe4208f | 329 | hash = ipv6_addr_hash(&sk->sk_v6_daddr); |
51c5d0c4 | 330 | break; |
c2bb06db | 331 | #endif |
51c5d0c4 DM |
332 | default: |
333 | return NULL; | |
334 | } | |
335 | ||
51c5d0c4 | 336 | net = dev_net(dst->dev); |
5815d5e7 | 337 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
51c5d0c4 | 338 | |
a5443028 | 339 | tm = __tcp_get_metrics(&saddr, &daddr, net, hash); |
77f99ad1 | 340 | if (tm == TCP_METRICS_RECLAIM_PTR) |
51c5d0c4 | 341 | tm = NULL; |
51c5d0c4 | 342 | if (!tm && create) |
41804420 | 343 | tm = tcpm_new(dst, &saddr, &daddr, hash); |
51c5d0c4 DM |
344 | else |
345 | tcpm_check_stamp(tm, dst); | |
346 | ||
347 | return tm; | |
348 | } | |
349 | ||
4aabd8ef DM |
350 | /* Save metrics learned by this TCP session. This function is called |
351 | * only, when TCP finishes successfully i.e. when it enters TIME-WAIT | |
352 | * or goes from LAST-ACK to CLOSE. | |
353 | */ | |
354 | void tcp_update_metrics(struct sock *sk) | |
355 | { | |
51c5d0c4 | 356 | const struct inet_connection_sock *icsk = inet_csk(sk); |
4aabd8ef | 357 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
358 | struct tcp_sock *tp = tcp_sk(sk); |
359 | struct tcp_metrics_block *tm; | |
360 | unsigned long rtt; | |
361 | u32 val; | |
362 | int m; | |
4aabd8ef | 363 | |
51c5d0c4 | 364 | if (sysctl_tcp_nometrics_save || !dst) |
4aabd8ef DM |
365 | return; |
366 | ||
51c5d0c4 | 367 | if (dst->flags & DST_HOST) |
4aabd8ef DM |
368 | dst_confirm(dst); |
369 | ||
51c5d0c4 DM |
370 | rcu_read_lock(); |
371 | if (icsk->icsk_backoff || !tp->srtt) { | |
372 | /* This session failed to estimate rtt. Why? | |
373 | * Probably, no packets returned in time. Reset our | |
374 | * results. | |
375 | */ | |
376 | tm = tcp_get_metrics(sk, dst, false); | |
377 | if (tm && !tcp_metric_locked(tm, TCP_METRIC_RTT)) | |
378 | tcp_metric_set(tm, TCP_METRIC_RTT, 0); | |
379 | goto out_unlock; | |
380 | } else | |
381 | tm = tcp_get_metrics(sk, dst, true); | |
4aabd8ef | 382 | |
51c5d0c4 DM |
383 | if (!tm) |
384 | goto out_unlock; | |
4aabd8ef | 385 | |
51c5d0c4 DM |
386 | rtt = tcp_metric_get_jiffies(tm, TCP_METRIC_RTT); |
387 | m = rtt - tp->srtt; | |
4aabd8ef | 388 | |
51c5d0c4 DM |
389 | /* If newly calculated rtt larger than stored one, store new |
390 | * one. Otherwise, use EWMA. Remember, rtt overestimation is | |
391 | * always better than underestimation. | |
392 | */ | |
393 | if (!tcp_metric_locked(tm, TCP_METRIC_RTT)) { | |
394 | if (m <= 0) | |
395 | rtt = tp->srtt; | |
396 | else | |
397 | rtt -= (m >> 3); | |
398 | tcp_metric_set_msecs(tm, TCP_METRIC_RTT, rtt); | |
399 | } | |
4aabd8ef | 400 | |
51c5d0c4 DM |
401 | if (!tcp_metric_locked(tm, TCP_METRIC_RTTVAR)) { |
402 | unsigned long var; | |
4aabd8ef | 403 | |
51c5d0c4 DM |
404 | if (m < 0) |
405 | m = -m; | |
4aabd8ef | 406 | |
51c5d0c4 DM |
407 | /* Scale deviation to rttvar fixed point */ |
408 | m >>= 1; | |
409 | if (m < tp->mdev) | |
410 | m = tp->mdev; | |
4aabd8ef | 411 | |
51c5d0c4 DM |
412 | var = tcp_metric_get_jiffies(tm, TCP_METRIC_RTTVAR); |
413 | if (m >= var) | |
414 | var = m; | |
415 | else | |
416 | var -= (var - m) >> 2; | |
4aabd8ef | 417 | |
51c5d0c4 DM |
418 | tcp_metric_set_msecs(tm, TCP_METRIC_RTTVAR, var); |
419 | } | |
420 | ||
421 | if (tcp_in_initial_slowstart(tp)) { | |
422 | /* Slow start still did not finish. */ | |
423 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { | |
424 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
425 | if (val && (tp->snd_cwnd >> 1) > val) | |
426 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
427 | tp->snd_cwnd >> 1); | |
428 | } | |
429 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
430 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
431 | if (tp->snd_cwnd > val) | |
432 | tcp_metric_set(tm, TCP_METRIC_CWND, | |
433 | tp->snd_cwnd); | |
434 | } | |
435 | } else if (tp->snd_cwnd > tp->snd_ssthresh && | |
436 | icsk->icsk_ca_state == TCP_CA_Open) { | |
437 | /* Cong. avoidance phase, cwnd is reliable. */ | |
438 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) | |
439 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
440 | max(tp->snd_cwnd >> 1, tp->snd_ssthresh)); | |
441 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
442 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
2100844c | 443 | tcp_metric_set(tm, TCP_METRIC_CWND, (val + tp->snd_cwnd) >> 1); |
51c5d0c4 DM |
444 | } |
445 | } else { | |
446 | /* Else slow start did not finish, cwnd is non-sense, | |
447 | * ssthresh may be also invalid. | |
448 | */ | |
449 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
450 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
451 | tcp_metric_set(tm, TCP_METRIC_CWND, | |
452 | (val + tp->snd_ssthresh) >> 1); | |
453 | } | |
454 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { | |
455 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
456 | if (val && tp->snd_ssthresh > val) | |
457 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
458 | tp->snd_ssthresh); | |
459 | } | |
460 | if (!tcp_metric_locked(tm, TCP_METRIC_REORDERING)) { | |
461 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); | |
462 | if (val < tp->reordering && | |
4aabd8ef | 463 | tp->reordering != sysctl_tcp_reordering) |
51c5d0c4 DM |
464 | tcp_metric_set(tm, TCP_METRIC_REORDERING, |
465 | tp->reordering); | |
4aabd8ef DM |
466 | } |
467 | } | |
51c5d0c4 DM |
468 | tm->tcpm_stamp = jiffies; |
469 | out_unlock: | |
470 | rcu_read_unlock(); | |
4aabd8ef DM |
471 | } |
472 | ||
473 | /* Initialize metrics on socket. */ | |
474 | ||
475 | void tcp_init_metrics(struct sock *sk) | |
476 | { | |
4aabd8ef | 477 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
478 | struct tcp_sock *tp = tcp_sk(sk); |
479 | struct tcp_metrics_block *tm; | |
1b7fdd2a | 480 | u32 val, crtt = 0; /* cached RTT scaled by 8 */ |
4aabd8ef DM |
481 | |
482 | if (dst == NULL) | |
483 | goto reset; | |
484 | ||
485 | dst_confirm(dst); | |
486 | ||
51c5d0c4 DM |
487 | rcu_read_lock(); |
488 | tm = tcp_get_metrics(sk, dst, true); | |
489 | if (!tm) { | |
490 | rcu_read_unlock(); | |
491 | goto reset; | |
492 | } | |
493 | ||
494 | if (tcp_metric_locked(tm, TCP_METRIC_CWND)) | |
495 | tp->snd_cwnd_clamp = tcp_metric_get(tm, TCP_METRIC_CWND); | |
496 | ||
497 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
498 | if (val) { | |
499 | tp->snd_ssthresh = val; | |
4aabd8ef DM |
500 | if (tp->snd_ssthresh > tp->snd_cwnd_clamp) |
501 | tp->snd_ssthresh = tp->snd_cwnd_clamp; | |
502 | } else { | |
503 | /* ssthresh may have been reduced unnecessarily during. | |
504 | * 3WHS. Restore it back to its initial default. | |
505 | */ | |
506 | tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; | |
507 | } | |
51c5d0c4 DM |
508 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); |
509 | if (val && tp->reordering != val) { | |
4aabd8ef DM |
510 | tcp_disable_fack(tp); |
511 | tcp_disable_early_retrans(tp); | |
51c5d0c4 | 512 | tp->reordering = val; |
4aabd8ef DM |
513 | } |
514 | ||
1b7fdd2a | 515 | crtt = tcp_metric_get_jiffies(tm, TCP_METRIC_RTT); |
51c5d0c4 | 516 | rcu_read_unlock(); |
4aabd8ef | 517 | reset: |
52f20e65 YC |
518 | /* The initial RTT measurement from the SYN/SYN-ACK is not ideal |
519 | * to seed the RTO for later data packets because SYN packets are | |
520 | * small. Use the per-dst cached values to seed the RTO but keep | |
521 | * the RTT estimator variables intact (e.g., srtt, mdev, rttvar). | |
522 | * Later the RTO will be updated immediately upon obtaining the first | |
523 | * data RTT sample (tcp_rtt_estimator()). Hence the cached RTT only | |
524 | * influences the first RTO but not later RTT estimation. | |
525 | * | |
526 | * But if RTT is not available from the SYN (due to retransmits or | |
527 | * syn cookies) or the cache, force a conservative 3secs timeout. | |
528 | * | |
529 | * A bit of theory. RTT is time passed after "normal" sized packet | |
530 | * is sent until it is ACKed. In normal circumstances sending small | |
531 | * packets force peer to delay ACKs and calculation is correct too. | |
532 | * The algorithm is adaptive and, provided we follow specs, it | |
533 | * NEVER underestimate RTT. BUT! If peer tries to make some clever | |
534 | * tricks sort of "quick acks" for time long enough to decrease RTT | |
535 | * to low value, and then abruptly stops to do it and starts to delay | |
536 | * ACKs, wait for troubles. | |
537 | */ | |
1b7fdd2a | 538 | if (crtt > tp->srtt) { |
269aa759 NC |
539 | /* Set RTO like tcp_rtt_estimator(), but from cached RTT. */ |
540 | crtt >>= 3; | |
541 | inet_csk(sk)->icsk_rto = crtt + max(2 * crtt, tcp_rto_min(sk)); | |
1b7fdd2a | 542 | } else if (tp->srtt == 0) { |
4aabd8ef DM |
543 | /* RFC6298: 5.7 We've failed to get a valid RTT sample from |
544 | * 3WHS. This is most likely due to retransmission, | |
545 | * including spurious one. Reset the RTO back to 3secs | |
546 | * from the more aggressive 1sec to avoid more spurious | |
547 | * retransmission. | |
548 | */ | |
549 | tp->mdev = tp->mdev_max = tp->rttvar = TCP_TIMEOUT_FALLBACK; | |
550 | inet_csk(sk)->icsk_rto = TCP_TIMEOUT_FALLBACK; | |
551 | } | |
552 | /* Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been | |
553 | * retransmitted. In light of RFC6298 more aggressive 1sec | |
554 | * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK | |
555 | * retransmission has occurred. | |
556 | */ | |
557 | if (tp->total_retrans > 1) | |
558 | tp->snd_cwnd = 1; | |
559 | else | |
560 | tp->snd_cwnd = tcp_init_cwnd(tp, dst); | |
561 | tp->snd_cwnd_stamp = tcp_time_stamp; | |
562 | } | |
ab92bb2f | 563 | |
81166dd6 | 564 | bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, bool paws_check) |
ab92bb2f | 565 | { |
51c5d0c4 DM |
566 | struct tcp_metrics_block *tm; |
567 | bool ret; | |
568 | ||
ab92bb2f DM |
569 | if (!dst) |
570 | return false; | |
51c5d0c4 DM |
571 | |
572 | rcu_read_lock(); | |
573 | tm = __tcp_get_metrics_req(req, dst); | |
81166dd6 DM |
574 | if (paws_check) { |
575 | if (tm && | |
576 | (u32)get_seconds() - tm->tcpm_ts_stamp < TCP_PAWS_MSL && | |
577 | (s32)(tm->tcpm_ts - req->ts_recent) > TCP_PAWS_WINDOW) | |
578 | ret = false; | |
579 | else | |
580 | ret = true; | |
581 | } else { | |
582 | if (tm && tcp_metric_get(tm, TCP_METRIC_RTT) && tm->tcpm_ts_stamp) | |
583 | ret = true; | |
584 | else | |
585 | ret = false; | |
586 | } | |
51c5d0c4 DM |
587 | rcu_read_unlock(); |
588 | ||
589 | return ret; | |
ab92bb2f DM |
590 | } |
591 | EXPORT_SYMBOL_GPL(tcp_peer_is_proven); | |
51c5d0c4 | 592 | |
81166dd6 DM |
593 | void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst) |
594 | { | |
595 | struct tcp_metrics_block *tm; | |
596 | ||
597 | rcu_read_lock(); | |
598 | tm = tcp_get_metrics(sk, dst, true); | |
599 | if (tm) { | |
600 | struct tcp_sock *tp = tcp_sk(sk); | |
601 | ||
602 | if ((u32)get_seconds() - tm->tcpm_ts_stamp <= TCP_PAWS_MSL) { | |
603 | tp->rx_opt.ts_recent_stamp = tm->tcpm_ts_stamp; | |
604 | tp->rx_opt.ts_recent = tm->tcpm_ts; | |
605 | } | |
606 | } | |
607 | rcu_read_unlock(); | |
608 | } | |
609 | EXPORT_SYMBOL_GPL(tcp_fetch_timewait_stamp); | |
610 | ||
611 | /* VJ's idea. Save last timestamp seen from this destination and hold | |
612 | * it at least for normal timewait interval to use for duplicate | |
613 | * segment detection in subsequent connections, before they enter | |
614 | * synchronized state. | |
615 | */ | |
616 | bool tcp_remember_stamp(struct sock *sk) | |
617 | { | |
618 | struct dst_entry *dst = __sk_dst_get(sk); | |
619 | bool ret = false; | |
620 | ||
621 | if (dst) { | |
622 | struct tcp_metrics_block *tm; | |
623 | ||
624 | rcu_read_lock(); | |
625 | tm = tcp_get_metrics(sk, dst, true); | |
626 | if (tm) { | |
627 | struct tcp_sock *tp = tcp_sk(sk); | |
628 | ||
629 | if ((s32)(tm->tcpm_ts - tp->rx_opt.ts_recent) <= 0 || | |
630 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && | |
631 | tm->tcpm_ts_stamp <= (u32)tp->rx_opt.ts_recent_stamp)) { | |
632 | tm->tcpm_ts_stamp = (u32)tp->rx_opt.ts_recent_stamp; | |
633 | tm->tcpm_ts = tp->rx_opt.ts_recent; | |
634 | } | |
635 | ret = true; | |
636 | } | |
637 | rcu_read_unlock(); | |
638 | } | |
639 | return ret; | |
640 | } | |
641 | ||
642 | bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw) | |
643 | { | |
644 | struct tcp_metrics_block *tm; | |
645 | bool ret = false; | |
646 | ||
647 | rcu_read_lock(); | |
648 | tm = __tcp_get_metrics_tw(tw); | |
9a0a9502 | 649 | if (tm) { |
81166dd6 DM |
650 | const struct tcp_timewait_sock *tcptw; |
651 | struct sock *sk = (struct sock *) tw; | |
652 | ||
653 | tcptw = tcp_twsk(sk); | |
654 | if ((s32)(tm->tcpm_ts - tcptw->tw_ts_recent) <= 0 || | |
655 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && | |
656 | tm->tcpm_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) { | |
657 | tm->tcpm_ts_stamp = (u32)tcptw->tw_ts_recent_stamp; | |
658 | tm->tcpm_ts = tcptw->tw_ts_recent; | |
659 | } | |
660 | ret = true; | |
661 | } | |
662 | rcu_read_unlock(); | |
663 | ||
664 | return ret; | |
665 | } | |
666 | ||
1fe4c481 YC |
667 | static DEFINE_SEQLOCK(fastopen_seqlock); |
668 | ||
669 | void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, | |
aab48743 YC |
670 | struct tcp_fastopen_cookie *cookie, |
671 | int *syn_loss, unsigned long *last_syn_loss) | |
1fe4c481 YC |
672 | { |
673 | struct tcp_metrics_block *tm; | |
674 | ||
675 | rcu_read_lock(); | |
676 | tm = tcp_get_metrics(sk, __sk_dst_get(sk), false); | |
677 | if (tm) { | |
678 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
679 | unsigned int seq; | |
680 | ||
681 | do { | |
682 | seq = read_seqbegin(&fastopen_seqlock); | |
683 | if (tfom->mss) | |
684 | *mss = tfom->mss; | |
685 | *cookie = tfom->cookie; | |
aab48743 YC |
686 | *syn_loss = tfom->syn_loss; |
687 | *last_syn_loss = *syn_loss ? tfom->last_syn_loss : 0; | |
1fe4c481 YC |
688 | } while (read_seqretry(&fastopen_seqlock, seq)); |
689 | } | |
690 | rcu_read_unlock(); | |
691 | } | |
692 | ||
1fe4c481 | 693 | void tcp_fastopen_cache_set(struct sock *sk, u16 mss, |
aab48743 | 694 | struct tcp_fastopen_cookie *cookie, bool syn_lost) |
1fe4c481 | 695 | { |
dccf76ca | 696 | struct dst_entry *dst = __sk_dst_get(sk); |
1fe4c481 YC |
697 | struct tcp_metrics_block *tm; |
698 | ||
dccf76ca ED |
699 | if (!dst) |
700 | return; | |
1fe4c481 | 701 | rcu_read_lock(); |
dccf76ca | 702 | tm = tcp_get_metrics(sk, dst, true); |
1fe4c481 YC |
703 | if (tm) { |
704 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
705 | ||
706 | write_seqlock_bh(&fastopen_seqlock); | |
c968601d YC |
707 | if (mss) |
708 | tfom->mss = mss; | |
709 | if (cookie && cookie->len > 0) | |
1fe4c481 | 710 | tfom->cookie = *cookie; |
aab48743 YC |
711 | if (syn_lost) { |
712 | ++tfom->syn_loss; | |
713 | tfom->last_syn_loss = jiffies; | |
714 | } else | |
715 | tfom->syn_loss = 0; | |
1fe4c481 YC |
716 | write_sequnlock_bh(&fastopen_seqlock); |
717 | } | |
718 | rcu_read_unlock(); | |
719 | } | |
720 | ||
d23ff701 JA |
721 | static struct genl_family tcp_metrics_nl_family = { |
722 | .id = GENL_ID_GENERATE, | |
723 | .hdrsize = 0, | |
724 | .name = TCP_METRICS_GENL_NAME, | |
725 | .version = TCP_METRICS_GENL_VERSION, | |
726 | .maxattr = TCP_METRICS_ATTR_MAX, | |
727 | .netnsok = true, | |
728 | }; | |
729 | ||
730 | static struct nla_policy tcp_metrics_nl_policy[TCP_METRICS_ATTR_MAX + 1] = { | |
731 | [TCP_METRICS_ATTR_ADDR_IPV4] = { .type = NLA_U32, }, | |
732 | [TCP_METRICS_ATTR_ADDR_IPV6] = { .type = NLA_BINARY, | |
733 | .len = sizeof(struct in6_addr), }, | |
734 | /* Following attributes are not received for GET/DEL, | |
735 | * we keep them for reference | |
736 | */ | |
737 | #if 0 | |
738 | [TCP_METRICS_ATTR_AGE] = { .type = NLA_MSECS, }, | |
739 | [TCP_METRICS_ATTR_TW_TSVAL] = { .type = NLA_U32, }, | |
740 | [TCP_METRICS_ATTR_TW_TS_STAMP] = { .type = NLA_S32, }, | |
741 | [TCP_METRICS_ATTR_VALS] = { .type = NLA_NESTED, }, | |
742 | [TCP_METRICS_ATTR_FOPEN_MSS] = { .type = NLA_U16, }, | |
743 | [TCP_METRICS_ATTR_FOPEN_SYN_DROPS] = { .type = NLA_U16, }, | |
744 | [TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS] = { .type = NLA_MSECS, }, | |
745 | [TCP_METRICS_ATTR_FOPEN_COOKIE] = { .type = NLA_BINARY, | |
746 | .len = TCP_FASTOPEN_COOKIE_MAX, }, | |
747 | #endif | |
748 | }; | |
749 | ||
750 | /* Add attributes, caller cancels its header on failure */ | |
751 | static int tcp_metrics_fill_info(struct sk_buff *msg, | |
752 | struct tcp_metrics_block *tm) | |
753 | { | |
754 | struct nlattr *nest; | |
755 | int i; | |
756 | ||
324fd55a | 757 | switch (tm->tcpm_daddr.family) { |
d23ff701 JA |
758 | case AF_INET: |
759 | if (nla_put_be32(msg, TCP_METRICS_ATTR_ADDR_IPV4, | |
324fd55a | 760 | tm->tcpm_daddr.addr.a4) < 0) |
d23ff701 | 761 | goto nla_put_failure; |
8a59359c CP |
762 | if (nla_put_be32(msg, TCP_METRICS_ATTR_SADDR_IPV4, |
763 | tm->tcpm_saddr.addr.a4) < 0) | |
764 | goto nla_put_failure; | |
d23ff701 JA |
765 | break; |
766 | case AF_INET6: | |
767 | if (nla_put(msg, TCP_METRICS_ATTR_ADDR_IPV6, 16, | |
324fd55a | 768 | tm->tcpm_daddr.addr.a6) < 0) |
d23ff701 | 769 | goto nla_put_failure; |
8a59359c CP |
770 | if (nla_put(msg, TCP_METRICS_ATTR_SADDR_IPV6, 16, |
771 | tm->tcpm_saddr.addr.a6) < 0) | |
772 | goto nla_put_failure; | |
d23ff701 JA |
773 | break; |
774 | default: | |
775 | return -EAFNOSUPPORT; | |
776 | } | |
777 | ||
778 | if (nla_put_msecs(msg, TCP_METRICS_ATTR_AGE, | |
779 | jiffies - tm->tcpm_stamp) < 0) | |
780 | goto nla_put_failure; | |
781 | if (tm->tcpm_ts_stamp) { | |
782 | if (nla_put_s32(msg, TCP_METRICS_ATTR_TW_TS_STAMP, | |
783 | (s32) (get_seconds() - tm->tcpm_ts_stamp)) < 0) | |
784 | goto nla_put_failure; | |
785 | if (nla_put_u32(msg, TCP_METRICS_ATTR_TW_TSVAL, | |
786 | tm->tcpm_ts) < 0) | |
787 | goto nla_put_failure; | |
788 | } | |
789 | ||
790 | { | |
791 | int n = 0; | |
792 | ||
793 | nest = nla_nest_start(msg, TCP_METRICS_ATTR_VALS); | |
794 | if (!nest) | |
795 | goto nla_put_failure; | |
796 | for (i = 0; i < TCP_METRIC_MAX + 1; i++) { | |
797 | if (!tm->tcpm_vals[i]) | |
798 | continue; | |
799 | if (nla_put_u32(msg, i + 1, tm->tcpm_vals[i]) < 0) | |
800 | goto nla_put_failure; | |
801 | n++; | |
802 | } | |
803 | if (n) | |
804 | nla_nest_end(msg, nest); | |
805 | else | |
806 | nla_nest_cancel(msg, nest); | |
807 | } | |
808 | ||
809 | { | |
810 | struct tcp_fastopen_metrics tfom_copy[1], *tfom; | |
811 | unsigned int seq; | |
812 | ||
813 | do { | |
814 | seq = read_seqbegin(&fastopen_seqlock); | |
815 | tfom_copy[0] = tm->tcpm_fastopen; | |
816 | } while (read_seqretry(&fastopen_seqlock, seq)); | |
817 | ||
818 | tfom = tfom_copy; | |
819 | if (tfom->mss && | |
820 | nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_MSS, | |
821 | tfom->mss) < 0) | |
822 | goto nla_put_failure; | |
823 | if (tfom->syn_loss && | |
824 | (nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROPS, | |
825 | tfom->syn_loss) < 0 || | |
826 | nla_put_msecs(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS, | |
827 | jiffies - tfom->last_syn_loss) < 0)) | |
828 | goto nla_put_failure; | |
829 | if (tfom->cookie.len > 0 && | |
830 | nla_put(msg, TCP_METRICS_ATTR_FOPEN_COOKIE, | |
831 | tfom->cookie.len, tfom->cookie.val) < 0) | |
832 | goto nla_put_failure; | |
833 | } | |
834 | ||
835 | return 0; | |
836 | ||
837 | nla_put_failure: | |
838 | return -EMSGSIZE; | |
839 | } | |
840 | ||
841 | static int tcp_metrics_dump_info(struct sk_buff *skb, | |
842 | struct netlink_callback *cb, | |
843 | struct tcp_metrics_block *tm) | |
844 | { | |
845 | void *hdr; | |
846 | ||
15e47304 | 847 | hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, |
d23ff701 JA |
848 | &tcp_metrics_nl_family, NLM_F_MULTI, |
849 | TCP_METRICS_CMD_GET); | |
850 | if (!hdr) | |
851 | return -EMSGSIZE; | |
852 | ||
853 | if (tcp_metrics_fill_info(skb, tm) < 0) | |
854 | goto nla_put_failure; | |
855 | ||
856 | return genlmsg_end(skb, hdr); | |
857 | ||
858 | nla_put_failure: | |
859 | genlmsg_cancel(skb, hdr); | |
860 | return -EMSGSIZE; | |
861 | } | |
862 | ||
863 | static int tcp_metrics_nl_dump(struct sk_buff *skb, | |
864 | struct netlink_callback *cb) | |
865 | { | |
866 | struct net *net = sock_net(skb->sk); | |
867 | unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; | |
868 | unsigned int row, s_row = cb->args[0]; | |
869 | int s_col = cb->args[1], col = s_col; | |
870 | ||
871 | for (row = s_row; row < max_rows; row++, s_col = 0) { | |
872 | struct tcp_metrics_block *tm; | |
873 | struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash + row; | |
874 | ||
875 | rcu_read_lock(); | |
876 | for (col = 0, tm = rcu_dereference(hb->chain); tm; | |
877 | tm = rcu_dereference(tm->tcpm_next), col++) { | |
878 | if (col < s_col) | |
879 | continue; | |
880 | if (tcp_metrics_dump_info(skb, cb, tm) < 0) { | |
881 | rcu_read_unlock(); | |
882 | goto done; | |
883 | } | |
884 | } | |
885 | rcu_read_unlock(); | |
886 | } | |
887 | ||
888 | done: | |
889 | cb->args[0] = row; | |
890 | cb->args[1] = col; | |
891 | return skb->len; | |
892 | } | |
893 | ||
3e7013dd CP |
894 | static int __parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
895 | unsigned int *hash, int optional, int v4, int v6) | |
d23ff701 JA |
896 | { |
897 | struct nlattr *a; | |
898 | ||
3e7013dd | 899 | a = info->attrs[v4]; |
d23ff701 JA |
900 | if (a) { |
901 | addr->family = AF_INET; | |
902 | addr->addr.a4 = nla_get_be32(a); | |
3e7013dd CP |
903 | if (hash) |
904 | *hash = (__force unsigned int) addr->addr.a4; | |
d23ff701 JA |
905 | return 0; |
906 | } | |
3e7013dd | 907 | a = info->attrs[v6]; |
d23ff701 | 908 | if (a) { |
2c42a3fb | 909 | if (nla_len(a) != sizeof(struct in6_addr)) |
d23ff701 JA |
910 | return -EINVAL; |
911 | addr->family = AF_INET6; | |
912 | memcpy(addr->addr.a6, nla_data(a), sizeof(addr->addr.a6)); | |
3e7013dd CP |
913 | if (hash) |
914 | *hash = ipv6_addr_hash((struct in6_addr *) addr->addr.a6); | |
d23ff701 JA |
915 | return 0; |
916 | } | |
917 | return optional ? 1 : -EAFNOSUPPORT; | |
918 | } | |
919 | ||
3e7013dd CP |
920 | static int parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
921 | unsigned int *hash, int optional) | |
922 | { | |
923 | return __parse_nl_addr(info, addr, hash, optional, | |
924 | TCP_METRICS_ATTR_ADDR_IPV4, | |
925 | TCP_METRICS_ATTR_ADDR_IPV6); | |
926 | } | |
927 | ||
928 | static int parse_nl_saddr(struct genl_info *info, struct inetpeer_addr *addr) | |
929 | { | |
930 | return __parse_nl_addr(info, addr, NULL, 0, | |
931 | TCP_METRICS_ATTR_SADDR_IPV4, | |
932 | TCP_METRICS_ATTR_SADDR_IPV6); | |
933 | } | |
934 | ||
d23ff701 JA |
935 | static int tcp_metrics_nl_cmd_get(struct sk_buff *skb, struct genl_info *info) |
936 | { | |
937 | struct tcp_metrics_block *tm; | |
3e7013dd | 938 | struct inetpeer_addr saddr, daddr; |
d23ff701 JA |
939 | unsigned int hash; |
940 | struct sk_buff *msg; | |
941 | struct net *net = genl_info_net(info); | |
942 | void *reply; | |
943 | int ret; | |
3e7013dd | 944 | bool src = true; |
d23ff701 | 945 | |
324fd55a | 946 | ret = parse_nl_addr(info, &daddr, &hash, 0); |
d23ff701 JA |
947 | if (ret < 0) |
948 | return ret; | |
949 | ||
3e7013dd CP |
950 | ret = parse_nl_saddr(info, &saddr); |
951 | if (ret < 0) | |
952 | src = false; | |
953 | ||
d23ff701 JA |
954 | msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
955 | if (!msg) | |
956 | return -ENOMEM; | |
957 | ||
958 | reply = genlmsg_put_reply(msg, info, &tcp_metrics_nl_family, 0, | |
959 | info->genlhdr->cmd); | |
960 | if (!reply) | |
961 | goto nla_put_failure; | |
962 | ||
963 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); | |
964 | ret = -ESRCH; | |
965 | rcu_read_lock(); | |
966 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
967 | tm = rcu_dereference(tm->tcpm_next)) { | |
3e7013dd CP |
968 | if (addr_same(&tm->tcpm_daddr, &daddr) && |
969 | (!src || addr_same(&tm->tcpm_saddr, &saddr))) { | |
d23ff701 JA |
970 | ret = tcp_metrics_fill_info(msg, tm); |
971 | break; | |
972 | } | |
973 | } | |
974 | rcu_read_unlock(); | |
975 | if (ret < 0) | |
976 | goto out_free; | |
977 | ||
978 | genlmsg_end(msg, reply); | |
979 | return genlmsg_reply(msg, info); | |
980 | ||
981 | nla_put_failure: | |
982 | ret = -EMSGSIZE; | |
983 | ||
984 | out_free: | |
985 | nlmsg_free(msg); | |
986 | return ret; | |
987 | } | |
988 | ||
989 | #define deref_locked_genl(p) \ | |
990 | rcu_dereference_protected(p, lockdep_genl_is_held() && \ | |
991 | lockdep_is_held(&tcp_metrics_lock)) | |
992 | ||
993 | #define deref_genl(p) rcu_dereference_protected(p, lockdep_genl_is_held()) | |
994 | ||
995 | static int tcp_metrics_flush_all(struct net *net) | |
996 | { | |
997 | unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; | |
998 | struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash; | |
999 | struct tcp_metrics_block *tm; | |
1000 | unsigned int row; | |
1001 | ||
1002 | for (row = 0; row < max_rows; row++, hb++) { | |
1003 | spin_lock_bh(&tcp_metrics_lock); | |
1004 | tm = deref_locked_genl(hb->chain); | |
1005 | if (tm) | |
1006 | hb->chain = NULL; | |
1007 | spin_unlock_bh(&tcp_metrics_lock); | |
1008 | while (tm) { | |
1009 | struct tcp_metrics_block *next; | |
1010 | ||
1011 | next = deref_genl(tm->tcpm_next); | |
1012 | kfree_rcu(tm, rcu_head); | |
1013 | tm = next; | |
1014 | } | |
1015 | } | |
1016 | return 0; | |
1017 | } | |
1018 | ||
1019 | static int tcp_metrics_nl_cmd_del(struct sk_buff *skb, struct genl_info *info) | |
1020 | { | |
1021 | struct tcpm_hash_bucket *hb; | |
00ca9c5b | 1022 | struct tcp_metrics_block *tm; |
d23ff701 | 1023 | struct tcp_metrics_block __rcu **pp; |
3e7013dd | 1024 | struct inetpeer_addr saddr, daddr; |
d23ff701 JA |
1025 | unsigned int hash; |
1026 | struct net *net = genl_info_net(info); | |
1027 | int ret; | |
00ca9c5b | 1028 | bool src = true, found = false; |
d23ff701 | 1029 | |
324fd55a | 1030 | ret = parse_nl_addr(info, &daddr, &hash, 1); |
d23ff701 JA |
1031 | if (ret < 0) |
1032 | return ret; | |
1033 | if (ret > 0) | |
1034 | return tcp_metrics_flush_all(net); | |
3e7013dd CP |
1035 | ret = parse_nl_saddr(info, &saddr); |
1036 | if (ret < 0) | |
1037 | src = false; | |
d23ff701 JA |
1038 | |
1039 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); | |
1040 | hb = net->ipv4.tcp_metrics_hash + hash; | |
1041 | pp = &hb->chain; | |
1042 | spin_lock_bh(&tcp_metrics_lock); | |
bbf852b9 | 1043 | for (tm = deref_locked_genl(*pp); tm; tm = deref_locked_genl(*pp)) { |
3e7013dd CP |
1044 | if (addr_same(&tm->tcpm_daddr, &daddr) && |
1045 | (!src || addr_same(&tm->tcpm_saddr, &saddr))) { | |
d23ff701 | 1046 | *pp = tm->tcpm_next; |
00ca9c5b CP |
1047 | kfree_rcu(tm, rcu_head); |
1048 | found = true; | |
bbf852b9 CP |
1049 | } else { |
1050 | pp = &tm->tcpm_next; | |
d23ff701 JA |
1051 | } |
1052 | } | |
1053 | spin_unlock_bh(&tcp_metrics_lock); | |
00ca9c5b | 1054 | if (!found) |
d23ff701 | 1055 | return -ESRCH; |
d23ff701 JA |
1056 | return 0; |
1057 | } | |
1058 | ||
4534de83 | 1059 | static const struct genl_ops tcp_metrics_nl_ops[] = { |
d23ff701 JA |
1060 | { |
1061 | .cmd = TCP_METRICS_CMD_GET, | |
1062 | .doit = tcp_metrics_nl_cmd_get, | |
1063 | .dumpit = tcp_metrics_nl_dump, | |
1064 | .policy = tcp_metrics_nl_policy, | |
1065 | .flags = GENL_ADMIN_PERM, | |
1066 | }, | |
1067 | { | |
1068 | .cmd = TCP_METRICS_CMD_DEL, | |
1069 | .doit = tcp_metrics_nl_cmd_del, | |
1070 | .policy = tcp_metrics_nl_policy, | |
1071 | .flags = GENL_ADMIN_PERM, | |
1072 | }, | |
1073 | }; | |
1074 | ||
5815d5e7 | 1075 | static unsigned int tcpmhash_entries; |
51c5d0c4 DM |
1076 | static int __init set_tcpmhash_entries(char *str) |
1077 | { | |
1078 | ssize_t ret; | |
1079 | ||
1080 | if (!str) | |
1081 | return 0; | |
1082 | ||
5815d5e7 | 1083 | ret = kstrtouint(str, 0, &tcpmhash_entries); |
51c5d0c4 DM |
1084 | if (ret) |
1085 | return 0; | |
1086 | ||
1087 | return 1; | |
1088 | } | |
1089 | __setup("tcpmhash_entries=", set_tcpmhash_entries); | |
1090 | ||
1091 | static int __net_init tcp_net_metrics_init(struct net *net) | |
1092 | { | |
5815d5e7 ED |
1093 | size_t size; |
1094 | unsigned int slots; | |
51c5d0c4 DM |
1095 | |
1096 | slots = tcpmhash_entries; | |
1097 | if (!slots) { | |
1098 | if (totalram_pages >= 128 * 1024) | |
1099 | slots = 16 * 1024; | |
1100 | else | |
1101 | slots = 8 * 1024; | |
1102 | } | |
1103 | ||
5815d5e7 ED |
1104 | net->ipv4.tcp_metrics_hash_log = order_base_2(slots); |
1105 | size = sizeof(struct tcpm_hash_bucket) << net->ipv4.tcp_metrics_hash_log; | |
51c5d0c4 | 1106 | |
976a702a ED |
1107 | net->ipv4.tcp_metrics_hash = kzalloc(size, GFP_KERNEL | __GFP_NOWARN); |
1108 | if (!net->ipv4.tcp_metrics_hash) | |
1109 | net->ipv4.tcp_metrics_hash = vzalloc(size); | |
1110 | ||
51c5d0c4 DM |
1111 | if (!net->ipv4.tcp_metrics_hash) |
1112 | return -ENOMEM; | |
1113 | ||
51c5d0c4 DM |
1114 | return 0; |
1115 | } | |
1116 | ||
1117 | static void __net_exit tcp_net_metrics_exit(struct net *net) | |
1118 | { | |
36471012 ED |
1119 | unsigned int i; |
1120 | ||
1121 | for (i = 0; i < (1U << net->ipv4.tcp_metrics_hash_log) ; i++) { | |
1122 | struct tcp_metrics_block *tm, *next; | |
1123 | ||
1124 | tm = rcu_dereference_protected(net->ipv4.tcp_metrics_hash[i].chain, 1); | |
1125 | while (tm) { | |
1126 | next = rcu_dereference_protected(tm->tcpm_next, 1); | |
1127 | kfree(tm); | |
1128 | tm = next; | |
1129 | } | |
1130 | } | |
976a702a ED |
1131 | if (is_vmalloc_addr(net->ipv4.tcp_metrics_hash)) |
1132 | vfree(net->ipv4.tcp_metrics_hash); | |
1133 | else | |
1134 | kfree(net->ipv4.tcp_metrics_hash); | |
51c5d0c4 DM |
1135 | } |
1136 | ||
1137 | static __net_initdata struct pernet_operations tcp_net_metrics_ops = { | |
1138 | .init = tcp_net_metrics_init, | |
1139 | .exit = tcp_net_metrics_exit, | |
1140 | }; | |
1141 | ||
1142 | void __init tcp_metrics_init(void) | |
1143 | { | |
d23ff701 JA |
1144 | int ret; |
1145 | ||
1146 | ret = register_pernet_subsys(&tcp_net_metrics_ops); | |
1147 | if (ret < 0) | |
1148 | goto cleanup; | |
1149 | ret = genl_register_family_with_ops(&tcp_metrics_nl_family, | |
c53ed742 | 1150 | tcp_metrics_nl_ops); |
d23ff701 JA |
1151 | if (ret < 0) |
1152 | goto cleanup_subsys; | |
1153 | return; | |
1154 | ||
1155 | cleanup_subsys: | |
1156 | unregister_pernet_subsys(&tcp_net_metrics_ops); | |
1157 | ||
1158 | cleanup: | |
1159 | return; | |
51c5d0c4 | 1160 | } |