Merge branch 'next' into for-linus
[linux-2.6-block.git] / net / rxrpc / peer_event.c
CommitLineData
f66d7490 1/* Peer event handling, typically ICMP messages.
17926a79
DH
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/module.h>
13#include <linux/net.h>
14#include <linux/skbuff.h>
15#include <linux/errqueue.h>
16#include <linux/udp.h>
17#include <linux/in.h>
18#include <linux/in6.h>
19#include <linux/icmp.h>
20#include <net/sock.h>
21#include <net/af_rxrpc.h>
22#include <net/ip.h>
23#include "ar-internal.h"
24
f66d7490 25static void rxrpc_store_error(struct rxrpc_peer *, struct sock_exterr_skb *);
f3344303
DH
26static void rxrpc_distribute_error(struct rxrpc_peer *, int,
27 enum rxrpc_call_completion);
f66d7490 28
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DH
29/*
30 * Find the peer associated with an ICMP packet.
31 */
32static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
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DH
33 const struct sk_buff *skb,
34 struct sockaddr_rxrpc *srx)
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DH
35{
36 struct sock_exterr_skb *serr = SKB_EXT_ERR(skb);
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37
38 _enter("");
39
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DH
40 memset(srx, 0, sizeof(*srx));
41 srx->transport_type = local->srx.transport_type;
42 srx->transport_len = local->srx.transport_len;
43 srx->transport.family = local->srx.transport.family;
be6e6707
DH
44
45 /* Can we see an ICMP4 packet on an ICMP6 listening socket? and vice
46 * versa?
47 */
494337c9 48 switch (srx->transport.family) {
be6e6707 49 case AF_INET:
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DH
50 srx->transport_len = sizeof(srx->transport.sin);
51 srx->transport.family = AF_INET;
494337c9 52 srx->transport.sin.sin_port = serr->port;
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DH
53 switch (serr->ee.ee_origin) {
54 case SO_EE_ORIGIN_ICMP:
55 _net("Rx ICMP");
494337c9 56 memcpy(&srx->transport.sin.sin_addr,
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DH
57 skb_network_header(skb) + serr->addr_offset,
58 sizeof(struct in_addr));
59 break;
60 case SO_EE_ORIGIN_ICMP6:
61 _net("Rx ICMP6 on v4 sock");
494337c9 62 memcpy(&srx->transport.sin.sin_addr,
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63 skb_network_header(skb) + serr->addr_offset + 12,
64 sizeof(struct in_addr));
65 break;
66 default:
494337c9 67 memcpy(&srx->transport.sin.sin_addr, &ip_hdr(skb)->saddr,
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DH
68 sizeof(struct in_addr));
69 break;
70 }
71 break;
72
d1912747 73#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 74 case AF_INET6:
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DH
75 switch (serr->ee.ee_origin) {
76 case SO_EE_ORIGIN_ICMP6:
77 _net("Rx ICMP6");
46894a13 78 srx->transport.sin6.sin6_port = serr->port;
494337c9 79 memcpy(&srx->transport.sin6.sin6_addr,
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DH
80 skb_network_header(skb) + serr->addr_offset,
81 sizeof(struct in6_addr));
82 break;
83 case SO_EE_ORIGIN_ICMP:
84 _net("Rx ICMP on v6 sock");
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DH
85 srx->transport_len = sizeof(srx->transport.sin);
86 srx->transport.family = AF_INET;
87 srx->transport.sin.sin_port = serr->port;
88 memcpy(&srx->transport.sin.sin_addr,
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DH
89 skb_network_header(skb) + serr->addr_offset,
90 sizeof(struct in_addr));
91 break;
92 default:
494337c9 93 memcpy(&srx->transport.sin6.sin6_addr,
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DH
94 &ipv6_hdr(skb)->saddr,
95 sizeof(struct in6_addr));
96 break;
97 }
98 break;
d1912747 99#endif
75b54cb5 100
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101 default:
102 BUG();
103 }
104
494337c9 105 return rxrpc_lookup_peer_rcu(local, srx);
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106}
107
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DH
108/*
109 * Handle an MTU/fragmentation problem.
110 */
111static void rxrpc_adjust_mtu(struct rxrpc_peer *peer, struct sock_exterr_skb *serr)
112{
113 u32 mtu = serr->ee.ee_info;
114
115 _net("Rx ICMP Fragmentation Needed (%d)", mtu);
116
117 /* wind down the local interface MTU */
118 if (mtu > 0 && peer->if_mtu == 65535 && mtu < peer->if_mtu) {
119 peer->if_mtu = mtu;
120 _net("I/F MTU %u", mtu);
121 }
122
123 if (mtu == 0) {
124 /* they didn't give us a size, estimate one */
125 mtu = peer->if_mtu;
126 if (mtu > 1500) {
127 mtu >>= 1;
128 if (mtu < 1500)
129 mtu = 1500;
130 } else {
131 mtu -= 100;
132 if (mtu < peer->hdrsize)
133 mtu = peer->hdrsize + 4;
134 }
135 }
136
137 if (mtu < peer->mtu) {
138 spin_lock_bh(&peer->lock);
139 peer->mtu = mtu;
140 peer->maxdata = peer->mtu - peer->hdrsize;
141 spin_unlock_bh(&peer->lock);
142 _net("Net MTU %u (maxdata %u)",
143 peer->mtu, peer->maxdata);
144 }
145}
146
17926a79 147/*
f66d7490 148 * Handle an error received on the local endpoint.
17926a79 149 */
abe89ef0 150void rxrpc_error_report(struct sock *sk)
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DH
151{
152 struct sock_exterr_skb *serr;
494337c9 153 struct sockaddr_rxrpc srx;
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DH
154 struct rxrpc_local *local = sk->sk_user_data;
155 struct rxrpc_peer *peer;
156 struct sk_buff *skb;
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DH
157
158 _enter("%p{%d}", sk, local->debug_id);
159
56d282d9
MD
160 /* Clear the outstanding error value on the socket so that it doesn't
161 * cause kernel_sendmsg() to return it later.
162 */
163 sock_error(sk);
164
364a9e93 165 skb = sock_dequeue_err_skb(sk);
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DH
166 if (!skb) {
167 _leave("UDP socket errqueue empty");
168 return;
169 }
71f3ca40 170 rxrpc_new_skb(skb, rxrpc_skb_rx_received);
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WB
171 serr = SKB_EXT_ERR(skb);
172 if (!skb->len && serr->ee.ee_origin == SO_EE_ORIGIN_TIMESTAMPING) {
49ca0d8b 173 _leave("UDP empty message");
71f3ca40 174 rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
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WB
175 return;
176 }
17926a79 177
be6e6707 178 rcu_read_lock();
494337c9 179 peer = rxrpc_lookup_peer_icmp_rcu(local, skb, &srx);
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DH
180 if (peer && !rxrpc_get_peer_maybe(peer))
181 peer = NULL;
182 if (!peer) {
183 rcu_read_unlock();
71f3ca40 184 rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
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DH
185 _leave(" [no peer]");
186 return;
187 }
188
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DH
189 trace_rxrpc_rx_icmp(peer, &serr->ee, &srx);
190
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DH
191 if ((serr->ee.ee_origin == SO_EE_ORIGIN_ICMP &&
192 serr->ee.ee_type == ICMP_DEST_UNREACH &&
193 serr->ee.ee_code == ICMP_FRAG_NEEDED)) {
194 rxrpc_adjust_mtu(peer, serr);
f66d7490 195 rcu_read_unlock();
71f3ca40 196 rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
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DH
197 rxrpc_put_peer(peer);
198 _leave(" [MTU update]");
199 return;
17926a79
DH
200 }
201
f66d7490 202 rxrpc_store_error(peer, serr);
be6e6707 203 rcu_read_unlock();
71f3ca40 204 rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
1890fea7 205 rxrpc_put_peer(peer);
17926a79 206
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DH
207 _leave("");
208}
209
210/*
f66d7490 211 * Map an error report to error codes on the peer record.
17926a79 212 */
f66d7490
DH
213static void rxrpc_store_error(struct rxrpc_peer *peer,
214 struct sock_exterr_skb *serr)
17926a79 215{
f3344303 216 enum rxrpc_call_completion compl = RXRPC_CALL_NETWORK_ERROR;
17926a79 217 struct sock_extended_err *ee;
c9d10c49 218 int err;
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DH
219
220 _enter("");
221
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DH
222 ee = &serr->ee;
223
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DH
224 err = ee->ee_errno;
225
226 switch (ee->ee_origin) {
227 case SO_EE_ORIGIN_ICMP:
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DH
228 switch (ee->ee_type) {
229 case ICMP_DEST_UNREACH:
230 switch (ee->ee_code) {
231 case ICMP_NET_UNREACH:
232 _net("Rx Received ICMP Network Unreachable");
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DH
233 break;
234 case ICMP_HOST_UNREACH:
235 _net("Rx Received ICMP Host Unreachable");
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DH
236 break;
237 case ICMP_PORT_UNREACH:
238 _net("Rx Received ICMP Port Unreachable");
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DH
239 break;
240 case ICMP_NET_UNKNOWN:
241 _net("Rx Received ICMP Unknown Network");
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DH
242 break;
243 case ICMP_HOST_UNKNOWN:
244 _net("Rx Received ICMP Unknown Host");
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DH
245 break;
246 default:
247 _net("Rx Received ICMP DestUnreach code=%u",
248 ee->ee_code);
249 break;
250 }
251 break;
252
253 case ICMP_TIME_EXCEEDED:
254 _net("Rx Received ICMP TTL Exceeded");
255 break;
256
257 default:
258 _proto("Rx Received ICMP error { type=%u code=%u }",
259 ee->ee_type, ee->ee_code);
260 break;
261 }
262 break;
263
f66d7490 264 case SO_EE_ORIGIN_NONE:
17926a79 265 case SO_EE_ORIGIN_LOCAL:
fe77d5fc 266 _proto("Rx Received local error { error=%d }", err);
f3344303 267 compl = RXRPC_CALL_LOCAL_ERROR;
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DH
268 break;
269
17926a79
DH
270 case SO_EE_ORIGIN_ICMP6:
271 default:
fe77d5fc 272 _proto("Rx Received error report { orig=%u }", ee->ee_origin);
17926a79
DH
273 break;
274 }
275
f3344303 276 rxrpc_distribute_error(peer, err, compl);
f66d7490
DH
277}
278
279/*
f3344303 280 * Distribute an error that occurred on a peer.
f66d7490 281 */
f3344303
DH
282static void rxrpc_distribute_error(struct rxrpc_peer *peer, int error,
283 enum rxrpc_call_completion compl)
f66d7490 284{
f66d7490 285 struct rxrpc_call *call;
17926a79 286
f3344303 287 hlist_for_each_entry_rcu(call, &peer->error_targets, error_link) {
e34d4234 288 rxrpc_see_call(call);
f3344303
DH
289 if (call->state < RXRPC_CALL_COMPLETE &&
290 rxrpc_set_call_completion(call, compl, 0, -error))
248f219c 291 rxrpc_notify_socket(call);
17926a79 292 }
17926a79 293}
cf1a6474
DH
294
295/*
296 * Add RTT information to cache. This is called in softirq mode and has
297 * exclusive access to the peer RTT data.
298 */
299void rxrpc_peer_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why,
300 rxrpc_serial_t send_serial, rxrpc_serial_t resp_serial,
301 ktime_t send_time, ktime_t resp_time)
302{
303 struct rxrpc_peer *peer = call->peer;
304 s64 rtt;
305 u64 sum = peer->rtt_sum, avg;
306 u8 cursor = peer->rtt_cursor, usage = peer->rtt_usage;
307
308 rtt = ktime_to_ns(ktime_sub(resp_time, send_time));
309 if (rtt < 0)
310 return;
311
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DH
312 spin_lock(&peer->rtt_input_lock);
313
cf1a6474
DH
314 /* Replace the oldest datum in the RTT buffer */
315 sum -= peer->rtt_cache[cursor];
316 sum += rtt;
317 peer->rtt_cache[cursor] = rtt;
318 peer->rtt_cursor = (cursor + 1) & (RXRPC_RTT_CACHE_SIZE - 1);
319 peer->rtt_sum = sum;
320 if (usage < RXRPC_RTT_CACHE_SIZE) {
321 usage++;
322 peer->rtt_usage = usage;
323 }
324
c1e15b49
DH
325 spin_unlock(&peer->rtt_input_lock);
326
cf1a6474
DH
327 /* Now recalculate the average */
328 if (usage == RXRPC_RTT_CACHE_SIZE) {
329 avg = sum / RXRPC_RTT_CACHE_SIZE;
330 } else {
331 avg = sum;
332 do_div(avg, usage);
333 }
334
c1e15b49 335 /* Don't need to update this under lock */
cf1a6474
DH
336 peer->rtt = avg;
337 trace_rxrpc_rtt_rx(call, why, send_serial, resp_serial, rtt,
338 usage, avg);
339}
ace45bec
DH
340
341/*
330bdcfa 342 * Perform keep-alive pings.
ace45bec 343 */
330bdcfa
DH
344static void rxrpc_peer_keepalive_dispatch(struct rxrpc_net *rxnet,
345 struct list_head *collector,
346 time64_t base,
347 u8 cursor)
ace45bec 348{
ace45bec 349 struct rxrpc_peer *peer;
330bdcfa
DH
350 const u8 mask = ARRAY_SIZE(rxnet->peer_keepalive) - 1;
351 time64_t keepalive_at;
352 int slot;
ace45bec 353
330bdcfa 354 spin_lock_bh(&rxnet->peer_hash_lock);
ace45bec 355
330bdcfa
DH
356 while (!list_empty(collector)) {
357 peer = list_entry(collector->next,
358 struct rxrpc_peer, keepalive_link);
ace45bec 359
330bdcfa
DH
360 list_del_init(&peer->keepalive_link);
361 if (!rxrpc_get_peer_maybe(peer))
362 continue;
ace45bec 363
ace45bec 364 spin_unlock_bh(&rxnet->peer_hash_lock);
ace45bec 365
330bdcfa
DH
366 keepalive_at = peer->last_tx_at + RXRPC_KEEPALIVE_TIME;
367 slot = keepalive_at - base;
368 _debug("%02x peer %u t=%d {%pISp}",
369 cursor, peer->debug_id, slot, &peer->srx.transport);
370
371 if (keepalive_at <= base ||
372 keepalive_at > base + RXRPC_KEEPALIVE_TIME) {
373 rxrpc_send_keepalive(peer);
374 slot = RXRPC_KEEPALIVE_TIME;
ace45bec
DH
375 }
376
330bdcfa
DH
377 /* A transmission to this peer occurred since last we examined
378 * it so put it into the appropriate future bucket.
379 */
380 slot += cursor;
381 slot &= mask;
382 spin_lock_bh(&rxnet->peer_hash_lock);
383 list_add_tail(&peer->keepalive_link,
384 &rxnet->peer_keepalive[slot & mask]);
385 rxrpc_put_peer(peer);
ace45bec
DH
386 }
387
ace45bec 388 spin_unlock_bh(&rxnet->peer_hash_lock);
330bdcfa 389}
ace45bec 390
330bdcfa
DH
391/*
392 * Perform keep-alive pings with VERSION packets to keep any NAT alive.
393 */
394void rxrpc_peer_keepalive_worker(struct work_struct *work)
395{
396 struct rxrpc_net *rxnet =
397 container_of(work, struct rxrpc_net, peer_keepalive_work);
398 const u8 mask = ARRAY_SIZE(rxnet->peer_keepalive) - 1;
399 time64_t base, now, delay;
400 u8 cursor, stop;
401 LIST_HEAD(collector);
ace45bec 402
330bdcfa
DH
403 now = ktime_get_seconds();
404 base = rxnet->peer_keepalive_base;
405 cursor = rxnet->peer_keepalive_cursor;
406 _enter("%lld,%u", base - now, cursor);
ace45bec 407
330bdcfa
DH
408 if (!rxnet->live)
409 return;
ace45bec 410
330bdcfa
DH
411 /* Remove to a temporary list all the peers that are currently lodged
412 * in expired buckets plus all new peers.
413 *
414 * Everything in the bucket at the cursor is processed this
415 * second; the bucket at cursor + 1 goes at now + 1s and so
416 * on...
ace45bec 417 */
ace45bec 418 spin_lock_bh(&rxnet->peer_hash_lock);
330bdcfa
DH
419 list_splice_init(&rxnet->peer_keepalive_new, &collector);
420
421 stop = cursor + ARRAY_SIZE(rxnet->peer_keepalive);
422 while (base <= now && (s8)(cursor - stop) < 0) {
423 list_splice_tail_init(&rxnet->peer_keepalive[cursor & mask],
424 &collector);
425 base++;
426 cursor++;
427 }
ace45bec 428
330bdcfa
DH
429 base = now;
430 spin_unlock_bh(&rxnet->peer_hash_lock);
ace45bec 431
ace45bec
DH
432 rxnet->peer_keepalive_base = base;
433 rxnet->peer_keepalive_cursor = cursor;
330bdcfa
DH
434 rxrpc_peer_keepalive_dispatch(rxnet, &collector, base, cursor);
435 ASSERT(list_empty(&collector));
436
437 /* Schedule the timer for the next occupied timeslot. */
438 cursor = rxnet->peer_keepalive_cursor;
439 stop = cursor + RXRPC_KEEPALIVE_TIME - 1;
440 for (; (s8)(cursor - stop) < 0; cursor++) {
441 if (!list_empty(&rxnet->peer_keepalive[cursor & mask]))
442 break;
443 base++;
444 }
445
446 now = ktime_get_seconds();
447 delay = base - now;
448 if (delay < 1)
449 delay = 1;
450 delay *= HZ;
451 if (rxnet->live)
452 timer_reduce(&rxnet->peer_keepalive_timer, jiffies + delay);
453
ace45bec
DH
454 _leave("");
455}