Commit | Line | Data |
---|---|---|
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; | |
2646c831 DL |
31 | u16 syn_loss:10, /* Recurring Fast Open SYN losses */ |
32 | try_exp:2; /* Request w/ exp. option (once) */ | |
aab48743 | 33 | unsigned long last_syn_loss; /* Last Fast Open SYN loss */ |
1fe4c481 YC |
34 | struct tcp_fastopen_cookie cookie; |
35 | }; | |
36 | ||
740b0f18 ED |
37 | /* TCP_METRIC_MAX includes 2 extra fields for userspace compatibility |
38 | * Kernel only stores RTT and RTTVAR in usec resolution | |
39 | */ | |
40 | #define TCP_METRIC_MAX_KERNEL (TCP_METRIC_MAX - 2) | |
41 | ||
51c5d0c4 DM |
42 | struct tcp_metrics_block { |
43 | struct tcp_metrics_block __rcu *tcpm_next; | |
849e8a0c | 44 | possible_net_t tcpm_net; |
a5443028 | 45 | struct inetpeer_addr tcpm_saddr; |
324fd55a | 46 | struct inetpeer_addr tcpm_daddr; |
51c5d0c4 | 47 | unsigned long tcpm_stamp; |
81166dd6 DM |
48 | u32 tcpm_ts; |
49 | u32 tcpm_ts_stamp; | |
51c5d0c4 | 50 | u32 tcpm_lock; |
740b0f18 | 51 | u32 tcpm_vals[TCP_METRIC_MAX_KERNEL + 1]; |
1fe4c481 | 52 | struct tcp_fastopen_metrics tcpm_fastopen; |
d23ff701 JA |
53 | |
54 | struct rcu_head rcu_head; | |
51c5d0c4 DM |
55 | }; |
56 | ||
849e8a0c EB |
57 | static inline struct net *tm_net(struct tcp_metrics_block *tm) |
58 | { | |
59 | return read_pnet(&tm->tcpm_net); | |
60 | } | |
61 | ||
51c5d0c4 DM |
62 | static bool tcp_metric_locked(struct tcp_metrics_block *tm, |
63 | enum tcp_metric_index idx) | |
64 | { | |
65 | return tm->tcpm_lock & (1 << idx); | |
66 | } | |
67 | ||
68 | static u32 tcp_metric_get(struct tcp_metrics_block *tm, | |
69 | enum tcp_metric_index idx) | |
70 | { | |
71 | return tm->tcpm_vals[idx]; | |
72 | } | |
73 | ||
51c5d0c4 DM |
74 | static void tcp_metric_set(struct tcp_metrics_block *tm, |
75 | enum tcp_metric_index idx, | |
76 | u32 val) | |
77 | { | |
78 | tm->tcpm_vals[idx] = val; | |
79 | } | |
80 | ||
51c5d0c4 DM |
81 | static bool addr_same(const struct inetpeer_addr *a, |
82 | const struct inetpeer_addr *b) | |
83 | { | |
d39d14ff | 84 | return inetpeer_addr_cmp(a, b) == 0; |
51c5d0c4 DM |
85 | } |
86 | ||
87 | struct tcpm_hash_bucket { | |
88 | struct tcp_metrics_block __rcu *chain; | |
89 | }; | |
90 | ||
098a697b EB |
91 | static struct tcpm_hash_bucket *tcp_metrics_hash __read_mostly; |
92 | static unsigned int tcp_metrics_hash_log __read_mostly; | |
93 | ||
51c5d0c4 DM |
94 | static DEFINE_SPINLOCK(tcp_metrics_lock); |
95 | ||
740b0f18 ED |
96 | static void tcpm_suck_dst(struct tcp_metrics_block *tm, |
97 | const struct dst_entry *dst, | |
efeaa555 | 98 | bool fastopen_clear) |
51c5d0c4 | 99 | { |
740b0f18 | 100 | u32 msval; |
51c5d0c4 DM |
101 | u32 val; |
102 | ||
9a0a9502 JA |
103 | tm->tcpm_stamp = jiffies; |
104 | ||
51c5d0c4 DM |
105 | val = 0; |
106 | if (dst_metric_locked(dst, RTAX_RTT)) | |
107 | val |= 1 << TCP_METRIC_RTT; | |
108 | if (dst_metric_locked(dst, RTAX_RTTVAR)) | |
109 | val |= 1 << TCP_METRIC_RTTVAR; | |
110 | if (dst_metric_locked(dst, RTAX_SSTHRESH)) | |
111 | val |= 1 << TCP_METRIC_SSTHRESH; | |
112 | if (dst_metric_locked(dst, RTAX_CWND)) | |
113 | val |= 1 << TCP_METRIC_CWND; | |
114 | if (dst_metric_locked(dst, RTAX_REORDERING)) | |
115 | val |= 1 << TCP_METRIC_REORDERING; | |
116 | tm->tcpm_lock = val; | |
117 | ||
740b0f18 ED |
118 | msval = dst_metric_raw(dst, RTAX_RTT); |
119 | tm->tcpm_vals[TCP_METRIC_RTT] = msval * USEC_PER_MSEC; | |
120 | ||
121 | msval = dst_metric_raw(dst, RTAX_RTTVAR); | |
122 | tm->tcpm_vals[TCP_METRIC_RTTVAR] = msval * USEC_PER_MSEC; | |
51c5d0c4 DM |
123 | tm->tcpm_vals[TCP_METRIC_SSTHRESH] = dst_metric_raw(dst, RTAX_SSTHRESH); |
124 | tm->tcpm_vals[TCP_METRIC_CWND] = dst_metric_raw(dst, RTAX_CWND); | |
125 | tm->tcpm_vals[TCP_METRIC_REORDERING] = dst_metric_raw(dst, RTAX_REORDERING); | |
81166dd6 DM |
126 | tm->tcpm_ts = 0; |
127 | tm->tcpm_ts_stamp = 0; | |
efeaa555 ED |
128 | if (fastopen_clear) { |
129 | tm->tcpm_fastopen.mss = 0; | |
130 | tm->tcpm_fastopen.syn_loss = 0; | |
2646c831 DL |
131 | tm->tcpm_fastopen.try_exp = 0; |
132 | tm->tcpm_fastopen.cookie.exp = false; | |
efeaa555 ED |
133 | tm->tcpm_fastopen.cookie.len = 0; |
134 | } | |
51c5d0c4 DM |
135 | } |
136 | ||
77f99ad1 CP |
137 | #define TCP_METRICS_TIMEOUT (60 * 60 * HZ) |
138 | ||
139 | static void tcpm_check_stamp(struct tcp_metrics_block *tm, struct dst_entry *dst) | |
140 | { | |
141 | if (tm && unlikely(time_after(jiffies, tm->tcpm_stamp + TCP_METRICS_TIMEOUT))) | |
142 | tcpm_suck_dst(tm, dst, false); | |
143 | } | |
144 | ||
145 | #define TCP_METRICS_RECLAIM_DEPTH 5 | |
146 | #define TCP_METRICS_RECLAIM_PTR (struct tcp_metrics_block *) 0x1UL | |
147 | ||
9f1ab186 ED |
148 | #define deref_locked(p) \ |
149 | rcu_dereference_protected(p, lockdep_is_held(&tcp_metrics_lock)) | |
150 | ||
51c5d0c4 | 151 | static struct tcp_metrics_block *tcpm_new(struct dst_entry *dst, |
a5443028 | 152 | struct inetpeer_addr *saddr, |
324fd55a | 153 | struct inetpeer_addr *daddr, |
77f99ad1 | 154 | unsigned int hash) |
51c5d0c4 DM |
155 | { |
156 | struct tcp_metrics_block *tm; | |
157 | struct net *net; | |
77f99ad1 | 158 | bool reclaim = false; |
51c5d0c4 DM |
159 | |
160 | spin_lock_bh(&tcp_metrics_lock); | |
161 | net = dev_net(dst->dev); | |
77f99ad1 CP |
162 | |
163 | /* While waiting for the spin-lock the cache might have been populated | |
164 | * with this entry and so we have to check again. | |
165 | */ | |
41804420 | 166 | tm = __tcp_get_metrics(saddr, daddr, net, hash); |
77f99ad1 CP |
167 | if (tm == TCP_METRICS_RECLAIM_PTR) { |
168 | reclaim = true; | |
169 | tm = NULL; | |
170 | } | |
171 | if (tm) { | |
172 | tcpm_check_stamp(tm, dst); | |
173 | goto out_unlock; | |
174 | } | |
175 | ||
51c5d0c4 DM |
176 | if (unlikely(reclaim)) { |
177 | struct tcp_metrics_block *oldest; | |
178 | ||
9f1ab186 ED |
179 | oldest = deref_locked(tcp_metrics_hash[hash].chain); |
180 | for (tm = deref_locked(oldest->tcpm_next); tm; | |
181 | tm = deref_locked(tm->tcpm_next)) { | |
51c5d0c4 DM |
182 | if (time_before(tm->tcpm_stamp, oldest->tcpm_stamp)) |
183 | oldest = tm; | |
184 | } | |
185 | tm = oldest; | |
186 | } else { | |
187 | tm = kmalloc(sizeof(*tm), GFP_ATOMIC); | |
188 | if (!tm) | |
189 | goto out_unlock; | |
190 | } | |
849e8a0c | 191 | write_pnet(&tm->tcpm_net, net); |
a5443028 | 192 | tm->tcpm_saddr = *saddr; |
324fd55a | 193 | tm->tcpm_daddr = *daddr; |
51c5d0c4 | 194 | |
efeaa555 | 195 | tcpm_suck_dst(tm, dst, true); |
51c5d0c4 DM |
196 | |
197 | if (likely(!reclaim)) { | |
098a697b EB |
198 | tm->tcpm_next = tcp_metrics_hash[hash].chain; |
199 | rcu_assign_pointer(tcp_metrics_hash[hash].chain, tm); | |
51c5d0c4 DM |
200 | } |
201 | ||
202 | out_unlock: | |
203 | spin_unlock_bh(&tcp_metrics_lock); | |
204 | return tm; | |
205 | } | |
206 | ||
51c5d0c4 DM |
207 | static struct tcp_metrics_block *tcp_get_encode(struct tcp_metrics_block *tm, int depth) |
208 | { | |
209 | if (tm) | |
210 | return tm; | |
211 | if (depth > TCP_METRICS_RECLAIM_DEPTH) | |
212 | return TCP_METRICS_RECLAIM_PTR; | |
213 | return NULL; | |
214 | } | |
215 | ||
a5443028 CP |
216 | static struct tcp_metrics_block *__tcp_get_metrics(const struct inetpeer_addr *saddr, |
217 | const struct inetpeer_addr *daddr, | |
51c5d0c4 DM |
218 | struct net *net, unsigned int hash) |
219 | { | |
220 | struct tcp_metrics_block *tm; | |
221 | int depth = 0; | |
222 | ||
098a697b | 223 | for (tm = rcu_dereference(tcp_metrics_hash[hash].chain); tm; |
51c5d0c4 | 224 | tm = rcu_dereference(tm->tcpm_next)) { |
a5443028 | 225 | if (addr_same(&tm->tcpm_saddr, saddr) && |
849e8a0c EB |
226 | addr_same(&tm->tcpm_daddr, daddr) && |
227 | net_eq(tm_net(tm), net)) | |
51c5d0c4 DM |
228 | break; |
229 | depth++; | |
230 | } | |
231 | return tcp_get_encode(tm, depth); | |
232 | } | |
233 | ||
234 | static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req, | |
235 | struct dst_entry *dst) | |
236 | { | |
237 | struct tcp_metrics_block *tm; | |
a5443028 | 238 | struct inetpeer_addr saddr, daddr; |
51c5d0c4 DM |
239 | unsigned int hash; |
240 | struct net *net; | |
241 | ||
a5443028 | 242 | saddr.family = req->rsk_ops->family; |
324fd55a CP |
243 | daddr.family = req->rsk_ops->family; |
244 | switch (daddr.family) { | |
51c5d0c4 | 245 | case AF_INET: |
3abef286 DA |
246 | inetpeer_set_addr_v4(&saddr, inet_rsk(req)->ir_loc_addr); |
247 | inetpeer_set_addr_v4(&daddr, inet_rsk(req)->ir_rmt_addr); | |
72afa352 | 248 | hash = ipv4_addr_hash(inet_rsk(req)->ir_rmt_addr); |
51c5d0c4 | 249 | break; |
634fb979 | 250 | #if IS_ENABLED(CONFIG_IPV6) |
51c5d0c4 | 251 | case AF_INET6: |
3abef286 DA |
252 | inetpeer_set_addr_v6(&saddr, &inet_rsk(req)->ir_v6_loc_addr); |
253 | inetpeer_set_addr_v6(&daddr, &inet_rsk(req)->ir_v6_rmt_addr); | |
634fb979 | 254 | hash = ipv6_addr_hash(&inet_rsk(req)->ir_v6_rmt_addr); |
51c5d0c4 | 255 | break; |
634fb979 | 256 | #endif |
51c5d0c4 DM |
257 | default: |
258 | return NULL; | |
259 | } | |
260 | ||
51c5d0c4 | 261 | net = dev_net(dst->dev); |
3e5da62d | 262 | hash ^= net_hash_mix(net); |
098a697b | 263 | hash = hash_32(hash, tcp_metrics_hash_log); |
51c5d0c4 | 264 | |
098a697b | 265 | for (tm = rcu_dereference(tcp_metrics_hash[hash].chain); tm; |
51c5d0c4 | 266 | tm = rcu_dereference(tm->tcpm_next)) { |
a5443028 | 267 | if (addr_same(&tm->tcpm_saddr, &saddr) && |
849e8a0c EB |
268 | addr_same(&tm->tcpm_daddr, &daddr) && |
269 | net_eq(tm_net(tm), net)) | |
51c5d0c4 DM |
270 | break; |
271 | } | |
272 | tcpm_check_stamp(tm, dst); | |
273 | return tm; | |
274 | } | |
275 | ||
81166dd6 DM |
276 | static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock *tw) |
277 | { | |
81166dd6 | 278 | struct tcp_metrics_block *tm; |
a5443028 | 279 | struct inetpeer_addr saddr, daddr; |
81166dd6 DM |
280 | unsigned int hash; |
281 | struct net *net; | |
282 | ||
3ad88cf7 | 283 | if (tw->tw_family == AF_INET) { |
3abef286 DA |
284 | inetpeer_set_addr_v4(&saddr, tw->tw_rcv_saddr); |
285 | inetpeer_set_addr_v4(&daddr, tw->tw_daddr); | |
72afa352 | 286 | hash = ipv4_addr_hash(tw->tw_daddr); |
3ad88cf7 | 287 | } |
c2bb06db | 288 | #if IS_ENABLED(CONFIG_IPV6) |
3ad88cf7 CP |
289 | else if (tw->tw_family == AF_INET6) { |
290 | if (ipv6_addr_v4mapped(&tw->tw_v6_daddr)) { | |
3abef286 DA |
291 | inetpeer_set_addr_v4(&saddr, tw->tw_rcv_saddr); |
292 | inetpeer_set_addr_v4(&daddr, tw->tw_daddr); | |
72afa352 | 293 | hash = ipv4_addr_hash(tw->tw_daddr); |
3ad88cf7 | 294 | } else { |
3abef286 DA |
295 | inetpeer_set_addr_v6(&saddr, &tw->tw_v6_rcv_saddr); |
296 | inetpeer_set_addr_v6(&daddr, &tw->tw_v6_daddr); | |
3ad88cf7 CP |
297 | hash = ipv6_addr_hash(&tw->tw_v6_daddr); |
298 | } | |
299 | } | |
c2bb06db | 300 | #endif |
3ad88cf7 | 301 | else |
81166dd6 | 302 | return NULL; |
81166dd6 | 303 | |
81166dd6 | 304 | net = twsk_net(tw); |
3e5da62d | 305 | hash ^= net_hash_mix(net); |
098a697b | 306 | hash = hash_32(hash, tcp_metrics_hash_log); |
81166dd6 | 307 | |
098a697b | 308 | for (tm = rcu_dereference(tcp_metrics_hash[hash].chain); tm; |
81166dd6 | 309 | tm = rcu_dereference(tm->tcpm_next)) { |
a5443028 | 310 | if (addr_same(&tm->tcpm_saddr, &saddr) && |
849e8a0c EB |
311 | addr_same(&tm->tcpm_daddr, &daddr) && |
312 | net_eq(tm_net(tm), net)) | |
81166dd6 DM |
313 | break; |
314 | } | |
315 | return tm; | |
316 | } | |
317 | ||
51c5d0c4 DM |
318 | static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk, |
319 | struct dst_entry *dst, | |
320 | bool create) | |
321 | { | |
322 | struct tcp_metrics_block *tm; | |
a5443028 | 323 | struct inetpeer_addr saddr, daddr; |
51c5d0c4 DM |
324 | unsigned int hash; |
325 | struct net *net; | |
51c5d0c4 | 326 | |
3ad88cf7 | 327 | if (sk->sk_family == AF_INET) { |
3abef286 DA |
328 | inetpeer_set_addr_v4(&saddr, inet_sk(sk)->inet_saddr); |
329 | inetpeer_set_addr_v4(&daddr, inet_sk(sk)->inet_daddr); | |
72afa352 | 330 | hash = ipv4_addr_hash(inet_sk(sk)->inet_daddr); |
3ad88cf7 | 331 | } |
c2bb06db | 332 | #if IS_ENABLED(CONFIG_IPV6) |
3ad88cf7 CP |
333 | else if (sk->sk_family == AF_INET6) { |
334 | if (ipv6_addr_v4mapped(&sk->sk_v6_daddr)) { | |
3abef286 DA |
335 | inetpeer_set_addr_v4(&saddr, inet_sk(sk)->inet_saddr); |
336 | inetpeer_set_addr_v4(&daddr, inet_sk(sk)->inet_daddr); | |
72afa352 | 337 | hash = ipv4_addr_hash(inet_sk(sk)->inet_daddr); |
3ad88cf7 | 338 | } else { |
3abef286 DA |
339 | inetpeer_set_addr_v6(&saddr, &sk->sk_v6_rcv_saddr); |
340 | inetpeer_set_addr_v6(&daddr, &sk->sk_v6_daddr); | |
3ad88cf7 CP |
341 | hash = ipv6_addr_hash(&sk->sk_v6_daddr); |
342 | } | |
343 | } | |
c2bb06db | 344 | #endif |
3ad88cf7 | 345 | else |
51c5d0c4 | 346 | return NULL; |
51c5d0c4 | 347 | |
51c5d0c4 | 348 | net = dev_net(dst->dev); |
3e5da62d | 349 | hash ^= net_hash_mix(net); |
098a697b | 350 | hash = hash_32(hash, tcp_metrics_hash_log); |
51c5d0c4 | 351 | |
a5443028 | 352 | tm = __tcp_get_metrics(&saddr, &daddr, net, hash); |
77f99ad1 | 353 | if (tm == TCP_METRICS_RECLAIM_PTR) |
51c5d0c4 | 354 | tm = NULL; |
51c5d0c4 | 355 | if (!tm && create) |
41804420 | 356 | tm = tcpm_new(dst, &saddr, &daddr, hash); |
51c5d0c4 DM |
357 | else |
358 | tcpm_check_stamp(tm, dst); | |
359 | ||
360 | return tm; | |
361 | } | |
362 | ||
4aabd8ef DM |
363 | /* Save metrics learned by this TCP session. This function is called |
364 | * only, when TCP finishes successfully i.e. when it enters TIME-WAIT | |
365 | * or goes from LAST-ACK to CLOSE. | |
366 | */ | |
367 | void tcp_update_metrics(struct sock *sk) | |
368 | { | |
51c5d0c4 | 369 | const struct inet_connection_sock *icsk = inet_csk(sk); |
4aabd8ef | 370 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
371 | struct tcp_sock *tp = tcp_sk(sk); |
372 | struct tcp_metrics_block *tm; | |
373 | unsigned long rtt; | |
374 | u32 val; | |
375 | int m; | |
4aabd8ef | 376 | |
51c5d0c4 | 377 | if (sysctl_tcp_nometrics_save || !dst) |
4aabd8ef DM |
378 | return; |
379 | ||
51c5d0c4 | 380 | if (dst->flags & DST_HOST) |
4aabd8ef DM |
381 | dst_confirm(dst); |
382 | ||
51c5d0c4 | 383 | rcu_read_lock(); |
740b0f18 | 384 | if (icsk->icsk_backoff || !tp->srtt_us) { |
51c5d0c4 DM |
385 | /* This session failed to estimate rtt. Why? |
386 | * Probably, no packets returned in time. Reset our | |
387 | * results. | |
388 | */ | |
389 | tm = tcp_get_metrics(sk, dst, false); | |
390 | if (tm && !tcp_metric_locked(tm, TCP_METRIC_RTT)) | |
391 | tcp_metric_set(tm, TCP_METRIC_RTT, 0); | |
392 | goto out_unlock; | |
393 | } else | |
394 | tm = tcp_get_metrics(sk, dst, true); | |
4aabd8ef | 395 | |
51c5d0c4 DM |
396 | if (!tm) |
397 | goto out_unlock; | |
4aabd8ef | 398 | |
740b0f18 ED |
399 | rtt = tcp_metric_get(tm, TCP_METRIC_RTT); |
400 | m = rtt - tp->srtt_us; | |
4aabd8ef | 401 | |
51c5d0c4 DM |
402 | /* If newly calculated rtt larger than stored one, store new |
403 | * one. Otherwise, use EWMA. Remember, rtt overestimation is | |
404 | * always better than underestimation. | |
405 | */ | |
406 | if (!tcp_metric_locked(tm, TCP_METRIC_RTT)) { | |
407 | if (m <= 0) | |
740b0f18 | 408 | rtt = tp->srtt_us; |
51c5d0c4 DM |
409 | else |
410 | rtt -= (m >> 3); | |
740b0f18 | 411 | tcp_metric_set(tm, TCP_METRIC_RTT, rtt); |
51c5d0c4 | 412 | } |
4aabd8ef | 413 | |
51c5d0c4 DM |
414 | if (!tcp_metric_locked(tm, TCP_METRIC_RTTVAR)) { |
415 | unsigned long var; | |
4aabd8ef | 416 | |
51c5d0c4 DM |
417 | if (m < 0) |
418 | m = -m; | |
4aabd8ef | 419 | |
51c5d0c4 DM |
420 | /* Scale deviation to rttvar fixed point */ |
421 | m >>= 1; | |
740b0f18 ED |
422 | if (m < tp->mdev_us) |
423 | m = tp->mdev_us; | |
4aabd8ef | 424 | |
740b0f18 | 425 | var = tcp_metric_get(tm, TCP_METRIC_RTTVAR); |
51c5d0c4 DM |
426 | if (m >= var) |
427 | var = m; | |
428 | else | |
429 | var -= (var - m) >> 2; | |
4aabd8ef | 430 | |
740b0f18 | 431 | tcp_metric_set(tm, TCP_METRIC_RTTVAR, var); |
51c5d0c4 DM |
432 | } |
433 | ||
434 | if (tcp_in_initial_slowstart(tp)) { | |
435 | /* Slow start still did not finish. */ | |
436 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { | |
437 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
438 | if (val && (tp->snd_cwnd >> 1) > val) | |
439 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
440 | tp->snd_cwnd >> 1); | |
441 | } | |
442 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
443 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
444 | if (tp->snd_cwnd > val) | |
445 | tcp_metric_set(tm, TCP_METRIC_CWND, | |
446 | tp->snd_cwnd); | |
447 | } | |
071d5080 | 448 | } else if (!tcp_in_slow_start(tp) && |
51c5d0c4 DM |
449 | icsk->icsk_ca_state == TCP_CA_Open) { |
450 | /* Cong. avoidance phase, cwnd is reliable. */ | |
451 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) | |
452 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
453 | max(tp->snd_cwnd >> 1, tp->snd_ssthresh)); | |
454 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
455 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
2100844c | 456 | tcp_metric_set(tm, TCP_METRIC_CWND, (val + tp->snd_cwnd) >> 1); |
51c5d0c4 DM |
457 | } |
458 | } else { | |
459 | /* Else slow start did not finish, cwnd is non-sense, | |
460 | * ssthresh may be also invalid. | |
461 | */ | |
462 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
463 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
464 | tcp_metric_set(tm, TCP_METRIC_CWND, | |
465 | (val + tp->snd_ssthresh) >> 1); | |
466 | } | |
467 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { | |
468 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
469 | if (val && tp->snd_ssthresh > val) | |
470 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
471 | tp->snd_ssthresh); | |
472 | } | |
473 | if (!tcp_metric_locked(tm, TCP_METRIC_REORDERING)) { | |
474 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); | |
475 | if (val < tp->reordering && | |
4aabd8ef | 476 | tp->reordering != sysctl_tcp_reordering) |
51c5d0c4 DM |
477 | tcp_metric_set(tm, TCP_METRIC_REORDERING, |
478 | tp->reordering); | |
4aabd8ef DM |
479 | } |
480 | } | |
51c5d0c4 DM |
481 | tm->tcpm_stamp = jiffies; |
482 | out_unlock: | |
483 | rcu_read_unlock(); | |
4aabd8ef DM |
484 | } |
485 | ||
486 | /* Initialize metrics on socket. */ | |
487 | ||
488 | void tcp_init_metrics(struct sock *sk) | |
489 | { | |
4aabd8ef | 490 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
491 | struct tcp_sock *tp = tcp_sk(sk); |
492 | struct tcp_metrics_block *tm; | |
1b7fdd2a | 493 | u32 val, crtt = 0; /* cached RTT scaled by 8 */ |
4aabd8ef | 494 | |
51456b29 | 495 | if (!dst) |
4aabd8ef DM |
496 | goto reset; |
497 | ||
498 | dst_confirm(dst); | |
499 | ||
51c5d0c4 DM |
500 | rcu_read_lock(); |
501 | tm = tcp_get_metrics(sk, dst, true); | |
502 | if (!tm) { | |
503 | rcu_read_unlock(); | |
504 | goto reset; | |
505 | } | |
506 | ||
507 | if (tcp_metric_locked(tm, TCP_METRIC_CWND)) | |
508 | tp->snd_cwnd_clamp = tcp_metric_get(tm, TCP_METRIC_CWND); | |
509 | ||
510 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
511 | if (val) { | |
512 | tp->snd_ssthresh = val; | |
4aabd8ef DM |
513 | if (tp->snd_ssthresh > tp->snd_cwnd_clamp) |
514 | tp->snd_ssthresh = tp->snd_cwnd_clamp; | |
515 | } else { | |
516 | /* ssthresh may have been reduced unnecessarily during. | |
517 | * 3WHS. Restore it back to its initial default. | |
518 | */ | |
519 | tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; | |
520 | } | |
51c5d0c4 DM |
521 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); |
522 | if (val && tp->reordering != val) { | |
4aabd8ef DM |
523 | tcp_disable_fack(tp); |
524 | tcp_disable_early_retrans(tp); | |
51c5d0c4 | 525 | tp->reordering = val; |
4aabd8ef DM |
526 | } |
527 | ||
740b0f18 | 528 | crtt = tcp_metric_get(tm, TCP_METRIC_RTT); |
51c5d0c4 | 529 | rcu_read_unlock(); |
4aabd8ef | 530 | reset: |
52f20e65 YC |
531 | /* The initial RTT measurement from the SYN/SYN-ACK is not ideal |
532 | * to seed the RTO for later data packets because SYN packets are | |
533 | * small. Use the per-dst cached values to seed the RTO but keep | |
534 | * the RTT estimator variables intact (e.g., srtt, mdev, rttvar). | |
535 | * Later the RTO will be updated immediately upon obtaining the first | |
536 | * data RTT sample (tcp_rtt_estimator()). Hence the cached RTT only | |
537 | * influences the first RTO but not later RTT estimation. | |
538 | * | |
539 | * But if RTT is not available from the SYN (due to retransmits or | |
540 | * syn cookies) or the cache, force a conservative 3secs timeout. | |
541 | * | |
542 | * A bit of theory. RTT is time passed after "normal" sized packet | |
543 | * is sent until it is ACKed. In normal circumstances sending small | |
544 | * packets force peer to delay ACKs and calculation is correct too. | |
545 | * The algorithm is adaptive and, provided we follow specs, it | |
546 | * NEVER underestimate RTT. BUT! If peer tries to make some clever | |
547 | * tricks sort of "quick acks" for time long enough to decrease RTT | |
548 | * to low value, and then abruptly stops to do it and starts to delay | |
549 | * ACKs, wait for troubles. | |
550 | */ | |
740b0f18 | 551 | if (crtt > tp->srtt_us) { |
269aa759 | 552 | /* Set RTO like tcp_rtt_estimator(), but from cached RTT. */ |
740b0f18 | 553 | crtt /= 8 * USEC_PER_MSEC; |
269aa759 | 554 | inet_csk(sk)->icsk_rto = crtt + max(2 * crtt, tcp_rto_min(sk)); |
740b0f18 | 555 | } else if (tp->srtt_us == 0) { |
4aabd8ef DM |
556 | /* RFC6298: 5.7 We've failed to get a valid RTT sample from |
557 | * 3WHS. This is most likely due to retransmission, | |
558 | * including spurious one. Reset the RTO back to 3secs | |
559 | * from the more aggressive 1sec to avoid more spurious | |
560 | * retransmission. | |
561 | */ | |
740b0f18 ED |
562 | tp->rttvar_us = jiffies_to_usecs(TCP_TIMEOUT_FALLBACK); |
563 | tp->mdev_us = tp->mdev_max_us = tp->rttvar_us; | |
564 | ||
4aabd8ef DM |
565 | inet_csk(sk)->icsk_rto = TCP_TIMEOUT_FALLBACK; |
566 | } | |
567 | /* Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been | |
568 | * retransmitted. In light of RFC6298 more aggressive 1sec | |
569 | * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK | |
570 | * retransmission has occurred. | |
571 | */ | |
572 | if (tp->total_retrans > 1) | |
573 | tp->snd_cwnd = 1; | |
574 | else | |
575 | tp->snd_cwnd = tcp_init_cwnd(tp, dst); | |
576 | tp->snd_cwnd_stamp = tcp_time_stamp; | |
577 | } | |
ab92bb2f | 578 | |
a26552af HFS |
579 | bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, |
580 | bool paws_check, bool timestamps) | |
ab92bb2f | 581 | { |
51c5d0c4 DM |
582 | struct tcp_metrics_block *tm; |
583 | bool ret; | |
584 | ||
ab92bb2f DM |
585 | if (!dst) |
586 | return false; | |
51c5d0c4 DM |
587 | |
588 | rcu_read_lock(); | |
589 | tm = __tcp_get_metrics_req(req, dst); | |
81166dd6 DM |
590 | if (paws_check) { |
591 | if (tm && | |
592 | (u32)get_seconds() - tm->tcpm_ts_stamp < TCP_PAWS_MSL && | |
a26552af HFS |
593 | ((s32)(tm->tcpm_ts - req->ts_recent) > TCP_PAWS_WINDOW || |
594 | !timestamps)) | |
81166dd6 DM |
595 | ret = false; |
596 | else | |
597 | ret = true; | |
598 | } else { | |
599 | if (tm && tcp_metric_get(tm, TCP_METRIC_RTT) && tm->tcpm_ts_stamp) | |
600 | ret = true; | |
601 | else | |
602 | ret = false; | |
603 | } | |
51c5d0c4 DM |
604 | rcu_read_unlock(); |
605 | ||
606 | return ret; | |
ab92bb2f DM |
607 | } |
608 | EXPORT_SYMBOL_GPL(tcp_peer_is_proven); | |
51c5d0c4 | 609 | |
81166dd6 DM |
610 | void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst) |
611 | { | |
612 | struct tcp_metrics_block *tm; | |
613 | ||
614 | rcu_read_lock(); | |
615 | tm = tcp_get_metrics(sk, dst, true); | |
616 | if (tm) { | |
617 | struct tcp_sock *tp = tcp_sk(sk); | |
618 | ||
619 | if ((u32)get_seconds() - tm->tcpm_ts_stamp <= TCP_PAWS_MSL) { | |
620 | tp->rx_opt.ts_recent_stamp = tm->tcpm_ts_stamp; | |
621 | tp->rx_opt.ts_recent = tm->tcpm_ts; | |
622 | } | |
623 | } | |
624 | rcu_read_unlock(); | |
625 | } | |
626 | EXPORT_SYMBOL_GPL(tcp_fetch_timewait_stamp); | |
627 | ||
628 | /* VJ's idea. Save last timestamp seen from this destination and hold | |
629 | * it at least for normal timewait interval to use for duplicate | |
630 | * segment detection in subsequent connections, before they enter | |
631 | * synchronized state. | |
632 | */ | |
633 | bool tcp_remember_stamp(struct sock *sk) | |
634 | { | |
635 | struct dst_entry *dst = __sk_dst_get(sk); | |
636 | bool ret = false; | |
637 | ||
638 | if (dst) { | |
639 | struct tcp_metrics_block *tm; | |
640 | ||
641 | rcu_read_lock(); | |
642 | tm = tcp_get_metrics(sk, dst, true); | |
643 | if (tm) { | |
644 | struct tcp_sock *tp = tcp_sk(sk); | |
645 | ||
646 | if ((s32)(tm->tcpm_ts - tp->rx_opt.ts_recent) <= 0 || | |
647 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && | |
648 | tm->tcpm_ts_stamp <= (u32)tp->rx_opt.ts_recent_stamp)) { | |
649 | tm->tcpm_ts_stamp = (u32)tp->rx_opt.ts_recent_stamp; | |
650 | tm->tcpm_ts = tp->rx_opt.ts_recent; | |
651 | } | |
652 | ret = true; | |
653 | } | |
654 | rcu_read_unlock(); | |
655 | } | |
656 | return ret; | |
657 | } | |
658 | ||
659 | bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw) | |
660 | { | |
661 | struct tcp_metrics_block *tm; | |
662 | bool ret = false; | |
663 | ||
664 | rcu_read_lock(); | |
665 | tm = __tcp_get_metrics_tw(tw); | |
9a0a9502 | 666 | if (tm) { |
81166dd6 DM |
667 | const struct tcp_timewait_sock *tcptw; |
668 | struct sock *sk = (struct sock *) tw; | |
669 | ||
670 | tcptw = tcp_twsk(sk); | |
671 | if ((s32)(tm->tcpm_ts - tcptw->tw_ts_recent) <= 0 || | |
672 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && | |
673 | tm->tcpm_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) { | |
674 | tm->tcpm_ts_stamp = (u32)tcptw->tw_ts_recent_stamp; | |
675 | tm->tcpm_ts = tcptw->tw_ts_recent; | |
676 | } | |
677 | ret = true; | |
678 | } | |
679 | rcu_read_unlock(); | |
680 | ||
681 | return ret; | |
682 | } | |
683 | ||
1fe4c481 YC |
684 | static DEFINE_SEQLOCK(fastopen_seqlock); |
685 | ||
686 | void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, | |
aab48743 YC |
687 | struct tcp_fastopen_cookie *cookie, |
688 | int *syn_loss, unsigned long *last_syn_loss) | |
1fe4c481 YC |
689 | { |
690 | struct tcp_metrics_block *tm; | |
691 | ||
692 | rcu_read_lock(); | |
693 | tm = tcp_get_metrics(sk, __sk_dst_get(sk), false); | |
694 | if (tm) { | |
695 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
696 | unsigned int seq; | |
697 | ||
698 | do { | |
699 | seq = read_seqbegin(&fastopen_seqlock); | |
700 | if (tfom->mss) | |
701 | *mss = tfom->mss; | |
702 | *cookie = tfom->cookie; | |
2646c831 DL |
703 | if (cookie->len <= 0 && tfom->try_exp == 1) |
704 | cookie->exp = true; | |
aab48743 YC |
705 | *syn_loss = tfom->syn_loss; |
706 | *last_syn_loss = *syn_loss ? tfom->last_syn_loss : 0; | |
1fe4c481 YC |
707 | } while (read_seqretry(&fastopen_seqlock, seq)); |
708 | } | |
709 | rcu_read_unlock(); | |
710 | } | |
711 | ||
1fe4c481 | 712 | void tcp_fastopen_cache_set(struct sock *sk, u16 mss, |
2646c831 DL |
713 | struct tcp_fastopen_cookie *cookie, bool syn_lost, |
714 | u16 try_exp) | |
1fe4c481 | 715 | { |
dccf76ca | 716 | struct dst_entry *dst = __sk_dst_get(sk); |
1fe4c481 YC |
717 | struct tcp_metrics_block *tm; |
718 | ||
dccf76ca ED |
719 | if (!dst) |
720 | return; | |
1fe4c481 | 721 | rcu_read_lock(); |
dccf76ca | 722 | tm = tcp_get_metrics(sk, dst, true); |
1fe4c481 YC |
723 | if (tm) { |
724 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
725 | ||
726 | write_seqlock_bh(&fastopen_seqlock); | |
c968601d YC |
727 | if (mss) |
728 | tfom->mss = mss; | |
729 | if (cookie && cookie->len > 0) | |
1fe4c481 | 730 | tfom->cookie = *cookie; |
2646c831 DL |
731 | else if (try_exp > tfom->try_exp && |
732 | tfom->cookie.len <= 0 && !tfom->cookie.exp) | |
733 | tfom->try_exp = try_exp; | |
aab48743 YC |
734 | if (syn_lost) { |
735 | ++tfom->syn_loss; | |
736 | tfom->last_syn_loss = jiffies; | |
737 | } else | |
738 | tfom->syn_loss = 0; | |
1fe4c481 YC |
739 | write_sequnlock_bh(&fastopen_seqlock); |
740 | } | |
741 | rcu_read_unlock(); | |
742 | } | |
743 | ||
d23ff701 JA |
744 | static struct genl_family tcp_metrics_nl_family = { |
745 | .id = GENL_ID_GENERATE, | |
746 | .hdrsize = 0, | |
747 | .name = TCP_METRICS_GENL_NAME, | |
748 | .version = TCP_METRICS_GENL_VERSION, | |
749 | .maxattr = TCP_METRICS_ATTR_MAX, | |
750 | .netnsok = true, | |
751 | }; | |
752 | ||
753 | static struct nla_policy tcp_metrics_nl_policy[TCP_METRICS_ATTR_MAX + 1] = { | |
754 | [TCP_METRICS_ATTR_ADDR_IPV4] = { .type = NLA_U32, }, | |
755 | [TCP_METRICS_ATTR_ADDR_IPV6] = { .type = NLA_BINARY, | |
756 | .len = sizeof(struct in6_addr), }, | |
757 | /* Following attributes are not received for GET/DEL, | |
758 | * we keep them for reference | |
759 | */ | |
760 | #if 0 | |
761 | [TCP_METRICS_ATTR_AGE] = { .type = NLA_MSECS, }, | |
762 | [TCP_METRICS_ATTR_TW_TSVAL] = { .type = NLA_U32, }, | |
763 | [TCP_METRICS_ATTR_TW_TS_STAMP] = { .type = NLA_S32, }, | |
764 | [TCP_METRICS_ATTR_VALS] = { .type = NLA_NESTED, }, | |
765 | [TCP_METRICS_ATTR_FOPEN_MSS] = { .type = NLA_U16, }, | |
766 | [TCP_METRICS_ATTR_FOPEN_SYN_DROPS] = { .type = NLA_U16, }, | |
767 | [TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS] = { .type = NLA_MSECS, }, | |
768 | [TCP_METRICS_ATTR_FOPEN_COOKIE] = { .type = NLA_BINARY, | |
769 | .len = TCP_FASTOPEN_COOKIE_MAX, }, | |
770 | #endif | |
771 | }; | |
772 | ||
773 | /* Add attributes, caller cancels its header on failure */ | |
774 | static int tcp_metrics_fill_info(struct sk_buff *msg, | |
775 | struct tcp_metrics_block *tm) | |
776 | { | |
777 | struct nlattr *nest; | |
778 | int i; | |
779 | ||
324fd55a | 780 | switch (tm->tcpm_daddr.family) { |
d23ff701 | 781 | case AF_INET: |
930345ea | 782 | if (nla_put_in_addr(msg, TCP_METRICS_ATTR_ADDR_IPV4, |
3abef286 | 783 | inetpeer_get_addr_v4(&tm->tcpm_daddr)) < 0) |
d23ff701 | 784 | goto nla_put_failure; |
930345ea | 785 | if (nla_put_in_addr(msg, TCP_METRICS_ATTR_SADDR_IPV4, |
3abef286 | 786 | inetpeer_get_addr_v4(&tm->tcpm_saddr)) < 0) |
8a59359c | 787 | goto nla_put_failure; |
d23ff701 JA |
788 | break; |
789 | case AF_INET6: | |
930345ea | 790 | if (nla_put_in6_addr(msg, TCP_METRICS_ATTR_ADDR_IPV6, |
3abef286 | 791 | inetpeer_get_addr_v6(&tm->tcpm_daddr)) < 0) |
d23ff701 | 792 | goto nla_put_failure; |
930345ea | 793 | if (nla_put_in6_addr(msg, TCP_METRICS_ATTR_SADDR_IPV6, |
3abef286 | 794 | inetpeer_get_addr_v6(&tm->tcpm_saddr)) < 0) |
8a59359c | 795 | goto nla_put_failure; |
d23ff701 JA |
796 | break; |
797 | default: | |
798 | return -EAFNOSUPPORT; | |
799 | } | |
800 | ||
801 | if (nla_put_msecs(msg, TCP_METRICS_ATTR_AGE, | |
802 | jiffies - tm->tcpm_stamp) < 0) | |
803 | goto nla_put_failure; | |
804 | if (tm->tcpm_ts_stamp) { | |
805 | if (nla_put_s32(msg, TCP_METRICS_ATTR_TW_TS_STAMP, | |
806 | (s32) (get_seconds() - tm->tcpm_ts_stamp)) < 0) | |
807 | goto nla_put_failure; | |
808 | if (nla_put_u32(msg, TCP_METRICS_ATTR_TW_TSVAL, | |
809 | tm->tcpm_ts) < 0) | |
810 | goto nla_put_failure; | |
811 | } | |
812 | ||
813 | { | |
814 | int n = 0; | |
815 | ||
816 | nest = nla_nest_start(msg, TCP_METRICS_ATTR_VALS); | |
817 | if (!nest) | |
818 | goto nla_put_failure; | |
740b0f18 ED |
819 | for (i = 0; i < TCP_METRIC_MAX_KERNEL + 1; i++) { |
820 | u32 val = tm->tcpm_vals[i]; | |
821 | ||
822 | if (!val) | |
d23ff701 | 823 | continue; |
740b0f18 ED |
824 | if (i == TCP_METRIC_RTT) { |
825 | if (nla_put_u32(msg, TCP_METRIC_RTT_US + 1, | |
826 | val) < 0) | |
827 | goto nla_put_failure; | |
828 | n++; | |
829 | val = max(val / 1000, 1U); | |
830 | } | |
831 | if (i == TCP_METRIC_RTTVAR) { | |
832 | if (nla_put_u32(msg, TCP_METRIC_RTTVAR_US + 1, | |
833 | val) < 0) | |
834 | goto nla_put_failure; | |
835 | n++; | |
836 | val = max(val / 1000, 1U); | |
837 | } | |
838 | if (nla_put_u32(msg, i + 1, val) < 0) | |
d23ff701 JA |
839 | goto nla_put_failure; |
840 | n++; | |
841 | } | |
842 | if (n) | |
843 | nla_nest_end(msg, nest); | |
844 | else | |
845 | nla_nest_cancel(msg, nest); | |
846 | } | |
847 | ||
848 | { | |
849 | struct tcp_fastopen_metrics tfom_copy[1], *tfom; | |
850 | unsigned int seq; | |
851 | ||
852 | do { | |
853 | seq = read_seqbegin(&fastopen_seqlock); | |
854 | tfom_copy[0] = tm->tcpm_fastopen; | |
855 | } while (read_seqretry(&fastopen_seqlock, seq)); | |
856 | ||
857 | tfom = tfom_copy; | |
858 | if (tfom->mss && | |
859 | nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_MSS, | |
860 | tfom->mss) < 0) | |
861 | goto nla_put_failure; | |
862 | if (tfom->syn_loss && | |
863 | (nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROPS, | |
864 | tfom->syn_loss) < 0 || | |
865 | nla_put_msecs(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS, | |
866 | jiffies - tfom->last_syn_loss) < 0)) | |
867 | goto nla_put_failure; | |
868 | if (tfom->cookie.len > 0 && | |
869 | nla_put(msg, TCP_METRICS_ATTR_FOPEN_COOKIE, | |
870 | tfom->cookie.len, tfom->cookie.val) < 0) | |
871 | goto nla_put_failure; | |
872 | } | |
873 | ||
874 | return 0; | |
875 | ||
876 | nla_put_failure: | |
877 | return -EMSGSIZE; | |
878 | } | |
879 | ||
880 | static int tcp_metrics_dump_info(struct sk_buff *skb, | |
881 | struct netlink_callback *cb, | |
882 | struct tcp_metrics_block *tm) | |
883 | { | |
884 | void *hdr; | |
885 | ||
15e47304 | 886 | hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, |
d23ff701 JA |
887 | &tcp_metrics_nl_family, NLM_F_MULTI, |
888 | TCP_METRICS_CMD_GET); | |
889 | if (!hdr) | |
890 | return -EMSGSIZE; | |
891 | ||
892 | if (tcp_metrics_fill_info(skb, tm) < 0) | |
893 | goto nla_put_failure; | |
894 | ||
053c095a JB |
895 | genlmsg_end(skb, hdr); |
896 | return 0; | |
d23ff701 JA |
897 | |
898 | nla_put_failure: | |
899 | genlmsg_cancel(skb, hdr); | |
900 | return -EMSGSIZE; | |
901 | } | |
902 | ||
903 | static int tcp_metrics_nl_dump(struct sk_buff *skb, | |
904 | struct netlink_callback *cb) | |
905 | { | |
906 | struct net *net = sock_net(skb->sk); | |
098a697b | 907 | unsigned int max_rows = 1U << tcp_metrics_hash_log; |
d23ff701 JA |
908 | unsigned int row, s_row = cb->args[0]; |
909 | int s_col = cb->args[1], col = s_col; | |
910 | ||
911 | for (row = s_row; row < max_rows; row++, s_col = 0) { | |
912 | struct tcp_metrics_block *tm; | |
098a697b | 913 | struct tcpm_hash_bucket *hb = tcp_metrics_hash + row; |
d23ff701 JA |
914 | |
915 | rcu_read_lock(); | |
916 | for (col = 0, tm = rcu_dereference(hb->chain); tm; | |
917 | tm = rcu_dereference(tm->tcpm_next), col++) { | |
849e8a0c EB |
918 | if (!net_eq(tm_net(tm), net)) |
919 | continue; | |
d23ff701 JA |
920 | if (col < s_col) |
921 | continue; | |
922 | if (tcp_metrics_dump_info(skb, cb, tm) < 0) { | |
923 | rcu_read_unlock(); | |
924 | goto done; | |
925 | } | |
926 | } | |
927 | rcu_read_unlock(); | |
928 | } | |
929 | ||
930 | done: | |
931 | cb->args[0] = row; | |
932 | cb->args[1] = col; | |
933 | return skb->len; | |
934 | } | |
935 | ||
3e7013dd CP |
936 | static int __parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
937 | unsigned int *hash, int optional, int v4, int v6) | |
d23ff701 JA |
938 | { |
939 | struct nlattr *a; | |
940 | ||
3e7013dd | 941 | a = info->attrs[v4]; |
d23ff701 | 942 | if (a) { |
3abef286 | 943 | inetpeer_set_addr_v4(addr, nla_get_in_addr(a)); |
3e7013dd | 944 | if (hash) |
3abef286 | 945 | *hash = ipv4_addr_hash(inetpeer_get_addr_v4(addr)); |
d23ff701 JA |
946 | return 0; |
947 | } | |
3e7013dd | 948 | a = info->attrs[v6]; |
d23ff701 | 949 | if (a) { |
3abef286 DA |
950 | struct in6_addr in6; |
951 | ||
2c42a3fb | 952 | if (nla_len(a) != sizeof(struct in6_addr)) |
d23ff701 | 953 | return -EINVAL; |
3abef286 DA |
954 | in6 = nla_get_in6_addr(a); |
955 | inetpeer_set_addr_v6(addr, &in6); | |
3e7013dd | 956 | if (hash) |
3abef286 | 957 | *hash = ipv6_addr_hash(inetpeer_get_addr_v6(addr)); |
d23ff701 JA |
958 | return 0; |
959 | } | |
960 | return optional ? 1 : -EAFNOSUPPORT; | |
961 | } | |
962 | ||
3e7013dd CP |
963 | static int parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
964 | unsigned int *hash, int optional) | |
965 | { | |
966 | return __parse_nl_addr(info, addr, hash, optional, | |
967 | TCP_METRICS_ATTR_ADDR_IPV4, | |
968 | TCP_METRICS_ATTR_ADDR_IPV6); | |
969 | } | |
970 | ||
971 | static int parse_nl_saddr(struct genl_info *info, struct inetpeer_addr *addr) | |
972 | { | |
973 | return __parse_nl_addr(info, addr, NULL, 0, | |
974 | TCP_METRICS_ATTR_SADDR_IPV4, | |
975 | TCP_METRICS_ATTR_SADDR_IPV6); | |
976 | } | |
977 | ||
d23ff701 JA |
978 | static int tcp_metrics_nl_cmd_get(struct sk_buff *skb, struct genl_info *info) |
979 | { | |
980 | struct tcp_metrics_block *tm; | |
3e7013dd | 981 | struct inetpeer_addr saddr, daddr; |
d23ff701 JA |
982 | unsigned int hash; |
983 | struct sk_buff *msg; | |
984 | struct net *net = genl_info_net(info); | |
985 | void *reply; | |
986 | int ret; | |
3e7013dd | 987 | bool src = true; |
d23ff701 | 988 | |
324fd55a | 989 | ret = parse_nl_addr(info, &daddr, &hash, 0); |
d23ff701 JA |
990 | if (ret < 0) |
991 | return ret; | |
992 | ||
3e7013dd CP |
993 | ret = parse_nl_saddr(info, &saddr); |
994 | if (ret < 0) | |
995 | src = false; | |
996 | ||
d23ff701 JA |
997 | msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
998 | if (!msg) | |
999 | return -ENOMEM; | |
1000 | ||
1001 | reply = genlmsg_put_reply(msg, info, &tcp_metrics_nl_family, 0, | |
1002 | info->genlhdr->cmd); | |
1003 | if (!reply) | |
1004 | goto nla_put_failure; | |
1005 | ||
3e5da62d | 1006 | hash ^= net_hash_mix(net); |
098a697b | 1007 | hash = hash_32(hash, tcp_metrics_hash_log); |
d23ff701 JA |
1008 | ret = -ESRCH; |
1009 | rcu_read_lock(); | |
098a697b | 1010 | for (tm = rcu_dereference(tcp_metrics_hash[hash].chain); tm; |
d23ff701 | 1011 | tm = rcu_dereference(tm->tcpm_next)) { |
3e7013dd | 1012 | if (addr_same(&tm->tcpm_daddr, &daddr) && |
849e8a0c EB |
1013 | (!src || addr_same(&tm->tcpm_saddr, &saddr)) && |
1014 | net_eq(tm_net(tm), net)) { | |
d23ff701 JA |
1015 | ret = tcp_metrics_fill_info(msg, tm); |
1016 | break; | |
1017 | } | |
1018 | } | |
1019 | rcu_read_unlock(); | |
1020 | if (ret < 0) | |
1021 | goto out_free; | |
1022 | ||
1023 | genlmsg_end(msg, reply); | |
1024 | return genlmsg_reply(msg, info); | |
1025 | ||
1026 | nla_put_failure: | |
1027 | ret = -EMSGSIZE; | |
1028 | ||
1029 | out_free: | |
1030 | nlmsg_free(msg); | |
1031 | return ret; | |
1032 | } | |
1033 | ||
8a4bff71 | 1034 | static void tcp_metrics_flush_all(struct net *net) |
d23ff701 | 1035 | { |
098a697b EB |
1036 | unsigned int max_rows = 1U << tcp_metrics_hash_log; |
1037 | struct tcpm_hash_bucket *hb = tcp_metrics_hash; | |
d23ff701 JA |
1038 | struct tcp_metrics_block *tm; |
1039 | unsigned int row; | |
1040 | ||
1041 | for (row = 0; row < max_rows; row++, hb++) { | |
04f721c6 | 1042 | struct tcp_metrics_block __rcu **pp; |
d23ff701 | 1043 | spin_lock_bh(&tcp_metrics_lock); |
04f721c6 | 1044 | pp = &hb->chain; |
9f1ab186 | 1045 | for (tm = deref_locked(*pp); tm; tm = deref_locked(*pp)) { |
04f721c6 EB |
1046 | if (net_eq(tm_net(tm), net)) { |
1047 | *pp = tm->tcpm_next; | |
1048 | kfree_rcu(tm, rcu_head); | |
1049 | } else { | |
1050 | pp = &tm->tcpm_next; | |
1051 | } | |
d23ff701 | 1052 | } |
04f721c6 | 1053 | spin_unlock_bh(&tcp_metrics_lock); |
d23ff701 | 1054 | } |
d23ff701 JA |
1055 | } |
1056 | ||
1057 | static int tcp_metrics_nl_cmd_del(struct sk_buff *skb, struct genl_info *info) | |
1058 | { | |
1059 | struct tcpm_hash_bucket *hb; | |
00ca9c5b | 1060 | struct tcp_metrics_block *tm; |
d23ff701 | 1061 | struct tcp_metrics_block __rcu **pp; |
3e7013dd | 1062 | struct inetpeer_addr saddr, daddr; |
d23ff701 JA |
1063 | unsigned int hash; |
1064 | struct net *net = genl_info_net(info); | |
1065 | int ret; | |
00ca9c5b | 1066 | bool src = true, found = false; |
d23ff701 | 1067 | |
324fd55a | 1068 | ret = parse_nl_addr(info, &daddr, &hash, 1); |
d23ff701 JA |
1069 | if (ret < 0) |
1070 | return ret; | |
8a4bff71 EB |
1071 | if (ret > 0) { |
1072 | tcp_metrics_flush_all(net); | |
1073 | return 0; | |
1074 | } | |
3e7013dd CP |
1075 | ret = parse_nl_saddr(info, &saddr); |
1076 | if (ret < 0) | |
1077 | src = false; | |
d23ff701 | 1078 | |
3e5da62d | 1079 | hash ^= net_hash_mix(net); |
098a697b EB |
1080 | hash = hash_32(hash, tcp_metrics_hash_log); |
1081 | hb = tcp_metrics_hash + hash; | |
d23ff701 JA |
1082 | pp = &hb->chain; |
1083 | spin_lock_bh(&tcp_metrics_lock); | |
9f1ab186 | 1084 | for (tm = deref_locked(*pp); tm; tm = deref_locked(*pp)) { |
3e7013dd | 1085 | if (addr_same(&tm->tcpm_daddr, &daddr) && |
849e8a0c EB |
1086 | (!src || addr_same(&tm->tcpm_saddr, &saddr)) && |
1087 | net_eq(tm_net(tm), net)) { | |
d23ff701 | 1088 | *pp = tm->tcpm_next; |
00ca9c5b CP |
1089 | kfree_rcu(tm, rcu_head); |
1090 | found = true; | |
bbf852b9 CP |
1091 | } else { |
1092 | pp = &tm->tcpm_next; | |
d23ff701 JA |
1093 | } |
1094 | } | |
1095 | spin_unlock_bh(&tcp_metrics_lock); | |
00ca9c5b | 1096 | if (!found) |
d23ff701 | 1097 | return -ESRCH; |
d23ff701 JA |
1098 | return 0; |
1099 | } | |
1100 | ||
4534de83 | 1101 | static const struct genl_ops tcp_metrics_nl_ops[] = { |
d23ff701 JA |
1102 | { |
1103 | .cmd = TCP_METRICS_CMD_GET, | |
1104 | .doit = tcp_metrics_nl_cmd_get, | |
1105 | .dumpit = tcp_metrics_nl_dump, | |
1106 | .policy = tcp_metrics_nl_policy, | |
d23ff701 JA |
1107 | }, |
1108 | { | |
1109 | .cmd = TCP_METRICS_CMD_DEL, | |
1110 | .doit = tcp_metrics_nl_cmd_del, | |
1111 | .policy = tcp_metrics_nl_policy, | |
1112 | .flags = GENL_ADMIN_PERM, | |
1113 | }, | |
1114 | }; | |
1115 | ||
5815d5e7 | 1116 | static unsigned int tcpmhash_entries; |
51c5d0c4 DM |
1117 | static int __init set_tcpmhash_entries(char *str) |
1118 | { | |
1119 | ssize_t ret; | |
1120 | ||
1121 | if (!str) | |
1122 | return 0; | |
1123 | ||
5815d5e7 | 1124 | ret = kstrtouint(str, 0, &tcpmhash_entries); |
51c5d0c4 DM |
1125 | if (ret) |
1126 | return 0; | |
1127 | ||
1128 | return 1; | |
1129 | } | |
1130 | __setup("tcpmhash_entries=", set_tcpmhash_entries); | |
1131 | ||
1132 | static int __net_init tcp_net_metrics_init(struct net *net) | |
1133 | { | |
5815d5e7 ED |
1134 | size_t size; |
1135 | unsigned int slots; | |
51c5d0c4 | 1136 | |
098a697b EB |
1137 | if (!net_eq(net, &init_net)) |
1138 | return 0; | |
1139 | ||
51c5d0c4 DM |
1140 | slots = tcpmhash_entries; |
1141 | if (!slots) { | |
1142 | if (totalram_pages >= 128 * 1024) | |
1143 | slots = 16 * 1024; | |
1144 | else | |
1145 | slots = 8 * 1024; | |
1146 | } | |
1147 | ||
098a697b EB |
1148 | tcp_metrics_hash_log = order_base_2(slots); |
1149 | size = sizeof(struct tcpm_hash_bucket) << tcp_metrics_hash_log; | |
51c5d0c4 | 1150 | |
098a697b EB |
1151 | tcp_metrics_hash = kzalloc(size, GFP_KERNEL | __GFP_NOWARN); |
1152 | if (!tcp_metrics_hash) | |
1153 | tcp_metrics_hash = vzalloc(size); | |
976a702a | 1154 | |
098a697b | 1155 | if (!tcp_metrics_hash) |
51c5d0c4 DM |
1156 | return -ENOMEM; |
1157 | ||
51c5d0c4 DM |
1158 | return 0; |
1159 | } | |
1160 | ||
1161 | static void __net_exit tcp_net_metrics_exit(struct net *net) | |
1162 | { | |
098a697b | 1163 | tcp_metrics_flush_all(net); |
51c5d0c4 DM |
1164 | } |
1165 | ||
1166 | static __net_initdata struct pernet_operations tcp_net_metrics_ops = { | |
1167 | .init = tcp_net_metrics_init, | |
1168 | .exit = tcp_net_metrics_exit, | |
1169 | }; | |
1170 | ||
1171 | void __init tcp_metrics_init(void) | |
1172 | { | |
d23ff701 JA |
1173 | int ret; |
1174 | ||
1175 | ret = register_pernet_subsys(&tcp_net_metrics_ops); | |
1176 | if (ret < 0) | |
6493517e EB |
1177 | panic("Could not allocate the tcp_metrics hash table\n"); |
1178 | ||
d23ff701 | 1179 | ret = genl_register_family_with_ops(&tcp_metrics_nl_family, |
c53ed742 | 1180 | tcp_metrics_nl_ops); |
d23ff701 | 1181 | if (ret < 0) |
6493517e | 1182 | panic("Could not register tcp_metrics generic netlink\n"); |
51c5d0c4 | 1183 | } |