]>
Commit | Line | Data |
---|---|---|
be6e6707 | 1 | /* RxRPC remote transport endpoint record management |
17926a79 | 2 | * |
be6e6707 | 3 | * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved. |
17926a79 DH |
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 | ||
9b6d5398 JP |
12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
13 | ||
17926a79 DH |
14 | #include <linux/module.h> |
15 | #include <linux/net.h> | |
16 | #include <linux/skbuff.h> | |
17 | #include <linux/udp.h> | |
18 | #include <linux/in.h> | |
75b54cb5 | 19 | #include <linux/in6.h> |
5a0e3ad6 | 20 | #include <linux/slab.h> |
be6e6707 | 21 | #include <linux/hashtable.h> |
17926a79 DH |
22 | #include <net/sock.h> |
23 | #include <net/af_rxrpc.h> | |
24 | #include <net/ip.h> | |
224711df | 25 | #include <net/route.h> |
75b54cb5 | 26 | #include <net/ip6_route.h> |
17926a79 DH |
27 | #include "ar-internal.h" |
28 | ||
be6e6707 DH |
29 | /* |
30 | * Hash a peer key. | |
31 | */ | |
32 | static unsigned long rxrpc_peer_hash_key(struct rxrpc_local *local, | |
33 | const struct sockaddr_rxrpc *srx) | |
34 | { | |
35 | const u16 *p; | |
36 | unsigned int i, size; | |
37 | unsigned long hash_key; | |
38 | ||
39 | _enter(""); | |
40 | ||
41 | hash_key = (unsigned long)local / __alignof__(*local); | |
42 | hash_key += srx->transport_type; | |
43 | hash_key += srx->transport_len; | |
44 | hash_key += srx->transport.family; | |
45 | ||
46 | switch (srx->transport.family) { | |
47 | case AF_INET: | |
48 | hash_key += (u16 __force)srx->transport.sin.sin_port; | |
49 | size = sizeof(srx->transport.sin.sin_addr); | |
50 | p = (u16 *)&srx->transport.sin.sin_addr; | |
51 | break; | |
d1912747 | 52 | #ifdef CONFIG_AF_RXRPC_IPV6 |
75b54cb5 DH |
53 | case AF_INET6: |
54 | hash_key += (u16 __force)srx->transport.sin.sin_port; | |
55 | size = sizeof(srx->transport.sin6.sin6_addr); | |
56 | p = (u16 *)&srx->transport.sin6.sin6_addr; | |
57 | break; | |
d1912747 | 58 | #endif |
2f9f9f52 AB |
59 | default: |
60 | WARN(1, "AF_RXRPC: Unsupported transport address family\n"); | |
61 | return 0; | |
be6e6707 DH |
62 | } |
63 | ||
64 | /* Step through the peer address in 16-bit portions for speed */ | |
65 | for (i = 0; i < size; i += sizeof(*p), p++) | |
66 | hash_key += *p; | |
67 | ||
68 | _leave(" 0x%lx", hash_key); | |
69 | return hash_key; | |
70 | } | |
71 | ||
72 | /* | |
73 | * Compare a peer to a key. Return -ve, 0 or +ve to indicate less than, same | |
74 | * or greater than. | |
75 | * | |
76 | * Unfortunately, the primitives in linux/hashtable.h don't allow for sorted | |
77 | * buckets and mid-bucket insertion, so we don't make full use of this | |
78 | * information at this point. | |
79 | */ | |
80 | static long rxrpc_peer_cmp_key(const struct rxrpc_peer *peer, | |
81 | struct rxrpc_local *local, | |
82 | const struct sockaddr_rxrpc *srx, | |
83 | unsigned long hash_key) | |
84 | { | |
85 | long diff; | |
86 | ||
87 | diff = ((peer->hash_key - hash_key) ?: | |
88 | ((unsigned long)peer->local - (unsigned long)local) ?: | |
89 | (peer->srx.transport_type - srx->transport_type) ?: | |
90 | (peer->srx.transport_len - srx->transport_len) ?: | |
91 | (peer->srx.transport.family - srx->transport.family)); | |
92 | if (diff != 0) | |
93 | return diff; | |
94 | ||
95 | switch (srx->transport.family) { | |
96 | case AF_INET: | |
97 | return ((u16 __force)peer->srx.transport.sin.sin_port - | |
98 | (u16 __force)srx->transport.sin.sin_port) ?: | |
99 | memcmp(&peer->srx.transport.sin.sin_addr, | |
100 | &srx->transport.sin.sin_addr, | |
101 | sizeof(struct in_addr)); | |
d1912747 | 102 | #ifdef CONFIG_AF_RXRPC_IPV6 |
75b54cb5 DH |
103 | case AF_INET6: |
104 | return ((u16 __force)peer->srx.transport.sin6.sin6_port - | |
105 | (u16 __force)srx->transport.sin6.sin6_port) ?: | |
106 | memcmp(&peer->srx.transport.sin6.sin6_addr, | |
107 | &srx->transport.sin6.sin6_addr, | |
108 | sizeof(struct in6_addr)); | |
d1912747 | 109 | #endif |
be6e6707 DH |
110 | default: |
111 | BUG(); | |
112 | } | |
113 | } | |
114 | ||
115 | /* | |
116 | * Look up a remote transport endpoint for the specified address using RCU. | |
117 | */ | |
118 | static struct rxrpc_peer *__rxrpc_lookup_peer_rcu( | |
119 | struct rxrpc_local *local, | |
120 | const struct sockaddr_rxrpc *srx, | |
121 | unsigned long hash_key) | |
122 | { | |
123 | struct rxrpc_peer *peer; | |
2baec2c3 | 124 | struct rxrpc_net *rxnet = local->rxnet; |
be6e6707 | 125 | |
2baec2c3 | 126 | hash_for_each_possible_rcu(rxnet->peer_hash, peer, hash_link, hash_key) { |
be6e6707 DH |
127 | if (rxrpc_peer_cmp_key(peer, local, srx, hash_key) == 0) { |
128 | if (atomic_read(&peer->usage) == 0) | |
129 | return NULL; | |
130 | return peer; | |
131 | } | |
132 | } | |
133 | ||
134 | return NULL; | |
135 | } | |
136 | ||
137 | /* | |
138 | * Look up a remote transport endpoint for the specified address using RCU. | |
139 | */ | |
140 | struct rxrpc_peer *rxrpc_lookup_peer_rcu(struct rxrpc_local *local, | |
141 | const struct sockaddr_rxrpc *srx) | |
142 | { | |
143 | struct rxrpc_peer *peer; | |
144 | unsigned long hash_key = rxrpc_peer_hash_key(local, srx); | |
145 | ||
146 | peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); | |
147 | if (peer) { | |
75b54cb5 | 148 | _net("PEER %d {%pISp}", peer->debug_id, &peer->srx.transport); |
be6e6707 DH |
149 | _leave(" = %p {u=%d}", peer, atomic_read(&peer->usage)); |
150 | } | |
151 | return peer; | |
152 | } | |
17926a79 | 153 | |
224711df DH |
154 | /* |
155 | * assess the MTU size for the network interface through which this peer is | |
156 | * reached | |
157 | */ | |
158 | static void rxrpc_assess_MTU_size(struct rxrpc_peer *peer) | |
159 | { | |
75b54cb5 | 160 | struct dst_entry *dst; |
224711df | 161 | struct rtable *rt; |
75b54cb5 DH |
162 | struct flowi fl; |
163 | struct flowi4 *fl4 = &fl.u.ip4; | |
d1912747 | 164 | #ifdef CONFIG_AF_RXRPC_IPV6 |
75b54cb5 | 165 | struct flowi6 *fl6 = &fl.u.ip6; |
d1912747 | 166 | #endif |
224711df DH |
167 | |
168 | peer->if_mtu = 1500; | |
169 | ||
75b54cb5 DH |
170 | memset(&fl, 0, sizeof(fl)); |
171 | switch (peer->srx.transport.family) { | |
172 | case AF_INET: | |
173 | rt = ip_route_output_ports( | |
174 | &init_net, fl4, NULL, | |
175 | peer->srx.transport.sin.sin_addr.s_addr, 0, | |
176 | htons(7000), htons(7001), IPPROTO_UDP, 0, 0); | |
177 | if (IS_ERR(rt)) { | |
178 | _leave(" [route err %ld]", PTR_ERR(rt)); | |
179 | return; | |
180 | } | |
181 | dst = &rt->dst; | |
182 | break; | |
183 | ||
d1912747 | 184 | #ifdef CONFIG_AF_RXRPC_IPV6 |
75b54cb5 DH |
185 | case AF_INET6: |
186 | fl6->flowi6_iif = LOOPBACK_IFINDEX; | |
187 | fl6->flowi6_scope = RT_SCOPE_UNIVERSE; | |
188 | fl6->flowi6_proto = IPPROTO_UDP; | |
189 | memcpy(&fl6->daddr, &peer->srx.transport.sin6.sin6_addr, | |
190 | sizeof(struct in6_addr)); | |
191 | fl6->fl6_dport = htons(7001); | |
192 | fl6->fl6_sport = htons(7000); | |
193 | dst = ip6_route_output(&init_net, NULL, fl6); | |
07096f61 DH |
194 | if (dst->error) { |
195 | _leave(" [route err %d]", dst->error); | |
75b54cb5 DH |
196 | return; |
197 | } | |
198 | break; | |
d1912747 | 199 | #endif |
75b54cb5 DH |
200 | |
201 | default: | |
202 | BUG(); | |
224711df DH |
203 | } |
204 | ||
75b54cb5 DH |
205 | peer->if_mtu = dst_mtu(dst); |
206 | dst_release(dst); | |
224711df | 207 | |
a6a62b69 | 208 | _leave(" [if_mtu %u]", peer->if_mtu); |
224711df DH |
209 | } |
210 | ||
17926a79 | 211 | /* |
be6e6707 | 212 | * Allocate a peer. |
17926a79 | 213 | */ |
be6e6707 | 214 | struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *local, gfp_t gfp) |
17926a79 DH |
215 | { |
216 | struct rxrpc_peer *peer; | |
217 | ||
218 | _enter(""); | |
219 | ||
220 | peer = kzalloc(sizeof(struct rxrpc_peer), gfp); | |
221 | if (peer) { | |
be6e6707 DH |
222 | atomic_set(&peer->usage, 1); |
223 | peer->local = local; | |
f66d7490 DH |
224 | INIT_HLIST_HEAD(&peer->error_targets); |
225 | INIT_WORK(&peer->error_distributor, | |
226 | &rxrpc_peer_error_distributor); | |
aa390bbe | 227 | peer->service_conns = RB_ROOT; |
8496af50 | 228 | seqlock_init(&peer->service_conn_lock); |
17926a79 | 229 | spin_lock_init(&peer->lock); |
17926a79 | 230 | peer->debug_id = atomic_inc_return(&rxrpc_debug_id); |
f7aec129 DH |
231 | |
232 | if (RXRPC_TX_SMSS > 2190) | |
233 | peer->cong_cwnd = 2; | |
234 | else if (RXRPC_TX_SMSS > 1095) | |
235 | peer->cong_cwnd = 3; | |
236 | else | |
237 | peer->cong_cwnd = 4; | |
be6e6707 DH |
238 | } |
239 | ||
240 | _leave(" = %p", peer); | |
241 | return peer; | |
242 | } | |
243 | ||
248f219c DH |
244 | /* |
245 | * Initialise peer record. | |
246 | */ | |
247 | static void rxrpc_init_peer(struct rxrpc_peer *peer, unsigned long hash_key) | |
248 | { | |
08a39685 | 249 | peer->hash_key = hash_key; |
248f219c DH |
250 | rxrpc_assess_MTU_size(peer); |
251 | peer->mtu = peer->if_mtu; | |
0d4b103c | 252 | peer->rtt_last_req = ktime_get_real(); |
248f219c | 253 | |
75b54cb5 DH |
254 | switch (peer->srx.transport.family) { |
255 | case AF_INET: | |
248f219c | 256 | peer->hdrsize = sizeof(struct iphdr); |
75b54cb5 | 257 | break; |
d1912747 | 258 | #ifdef CONFIG_AF_RXRPC_IPV6 |
75b54cb5 DH |
259 | case AF_INET6: |
260 | peer->hdrsize = sizeof(struct ipv6hdr); | |
261 | break; | |
d1912747 | 262 | #endif |
75b54cb5 DH |
263 | default: |
264 | BUG(); | |
265 | } | |
266 | ||
267 | switch (peer->srx.transport_type) { | |
268 | case SOCK_DGRAM: | |
269 | peer->hdrsize += sizeof(struct udphdr); | |
270 | break; | |
271 | default: | |
248f219c DH |
272 | BUG(); |
273 | } | |
274 | ||
275 | peer->hdrsize += sizeof(struct rxrpc_wire_header); | |
276 | peer->maxdata = peer->mtu - peer->hdrsize; | |
277 | } | |
278 | ||
be6e6707 DH |
279 | /* |
280 | * Set up a new peer. | |
281 | */ | |
282 | static struct rxrpc_peer *rxrpc_create_peer(struct rxrpc_local *local, | |
283 | struct sockaddr_rxrpc *srx, | |
284 | unsigned long hash_key, | |
285 | gfp_t gfp) | |
286 | { | |
287 | struct rxrpc_peer *peer; | |
288 | ||
289 | _enter(""); | |
290 | ||
291 | peer = rxrpc_alloc_peer(local, gfp); | |
292 | if (peer) { | |
17926a79 | 293 | memcpy(&peer->srx, srx, sizeof(*srx)); |
248f219c DH |
294 | rxrpc_init_peer(peer, hash_key); |
295 | } | |
17926a79 | 296 | |
248f219c DH |
297 | _leave(" = %p", peer); |
298 | return peer; | |
299 | } | |
17926a79 | 300 | |
248f219c DH |
301 | /* |
302 | * Set up a new incoming peer. The address is prestored in the preallocated | |
303 | * peer. | |
304 | */ | |
305 | struct rxrpc_peer *rxrpc_lookup_incoming_peer(struct rxrpc_local *local, | |
306 | struct rxrpc_peer *prealloc) | |
307 | { | |
308 | struct rxrpc_peer *peer; | |
2baec2c3 | 309 | struct rxrpc_net *rxnet = local->rxnet; |
248f219c DH |
310 | unsigned long hash_key; |
311 | ||
312 | hash_key = rxrpc_peer_hash_key(local, &prealloc->srx); | |
313 | prealloc->local = local; | |
314 | rxrpc_init_peer(prealloc, hash_key); | |
315 | ||
2baec2c3 | 316 | spin_lock(&rxnet->peer_hash_lock); |
248f219c DH |
317 | |
318 | /* Need to check that we aren't racing with someone else */ | |
319 | peer = __rxrpc_lookup_peer_rcu(local, &prealloc->srx, hash_key); | |
320 | if (peer && !rxrpc_get_peer_maybe(peer)) | |
321 | peer = NULL; | |
322 | if (!peer) { | |
323 | peer = prealloc; | |
2baec2c3 | 324 | hash_add_rcu(rxnet->peer_hash, &peer->hash_link, hash_key); |
17926a79 DH |
325 | } |
326 | ||
2baec2c3 | 327 | spin_unlock(&rxnet->peer_hash_lock); |
17926a79 DH |
328 | return peer; |
329 | } | |
330 | ||
331 | /* | |
332 | * obtain a remote transport endpoint for the specified address | |
333 | */ | |
be6e6707 DH |
334 | struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *local, |
335 | struct sockaddr_rxrpc *srx, gfp_t gfp) | |
17926a79 DH |
336 | { |
337 | struct rxrpc_peer *peer, *candidate; | |
2baec2c3 | 338 | struct rxrpc_net *rxnet = local->rxnet; |
be6e6707 | 339 | unsigned long hash_key = rxrpc_peer_hash_key(local, srx); |
17926a79 | 340 | |
75b54cb5 | 341 | _enter("{%pISp}", &srx->transport); |
17926a79 DH |
342 | |
343 | /* search the peer list first */ | |
be6e6707 DH |
344 | rcu_read_lock(); |
345 | peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); | |
346 | if (peer && !rxrpc_get_peer_maybe(peer)) | |
347 | peer = NULL; | |
348 | rcu_read_unlock(); | |
349 | ||
350 | if (!peer) { | |
351 | /* The peer is not yet present in hash - create a candidate | |
352 | * for a new record and then redo the search. | |
353 | */ | |
354 | candidate = rxrpc_create_peer(local, srx, hash_key, gfp); | |
355 | if (!candidate) { | |
356 | _leave(" = NULL [nomem]"); | |
357 | return NULL; | |
358 | } | |
17926a79 | 359 | |
2baec2c3 | 360 | spin_lock_bh(&rxnet->peer_hash_lock); |
17926a79 | 361 | |
be6e6707 DH |
362 | /* Need to check that we aren't racing with someone else */ |
363 | peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); | |
364 | if (peer && !rxrpc_get_peer_maybe(peer)) | |
365 | peer = NULL; | |
366 | if (!peer) | |
2baec2c3 | 367 | hash_add_rcu(rxnet->peer_hash, |
be6e6707 | 368 | &candidate->hash_link, hash_key); |
17926a79 | 369 | |
2baec2c3 | 370 | spin_unlock_bh(&rxnet->peer_hash_lock); |
17926a79 | 371 | |
be6e6707 DH |
372 | if (peer) |
373 | kfree(candidate); | |
374 | else | |
375 | peer = candidate; | |
376 | } | |
17926a79 | 377 | |
75b54cb5 | 378 | _net("PEER %d {%pISp}", peer->debug_id, &peer->srx.transport); |
17926a79 | 379 | |
be6e6707 | 380 | _leave(" = %p {u=%d}", peer, atomic_read(&peer->usage)); |
17926a79 | 381 | return peer; |
17926a79 DH |
382 | } |
383 | ||
384 | /* | |
be6e6707 | 385 | * Discard a ref on a remote peer record. |
17926a79 | 386 | */ |
be6e6707 | 387 | void __rxrpc_put_peer(struct rxrpc_peer *peer) |
17926a79 | 388 | { |
2baec2c3 DH |
389 | struct rxrpc_net *rxnet = peer->local->rxnet; |
390 | ||
f66d7490 | 391 | ASSERT(hlist_empty(&peer->error_targets)); |
17926a79 | 392 | |
2baec2c3 | 393 | spin_lock_bh(&rxnet->peer_hash_lock); |
be6e6707 | 394 | hash_del_rcu(&peer->hash_link); |
2baec2c3 | 395 | spin_unlock_bh(&rxnet->peer_hash_lock); |
17926a79 | 396 | |
be6e6707 | 397 | kfree_rcu(peer, rcu); |
17926a79 | 398 | } |
8324f0bc DH |
399 | |
400 | /** | |
401 | * rxrpc_kernel_get_peer - Get the peer address of a call | |
402 | * @sock: The socket on which the call is in progress. | |
403 | * @call: The call to query | |
404 | * @_srx: Where to place the result | |
405 | * | |
406 | * Get the address of the remote peer in a call. | |
407 | */ | |
408 | void rxrpc_kernel_get_peer(struct socket *sock, struct rxrpc_call *call, | |
409 | struct sockaddr_rxrpc *_srx) | |
410 | { | |
411 | *_srx = call->peer->srx; | |
412 | } | |
413 | EXPORT_SYMBOL(rxrpc_kernel_get_peer); | |
f4d15fb6 DH |
414 | |
415 | /** | |
416 | * rxrpc_kernel_get_rtt - Get a call's peer RTT | |
417 | * @sock: The socket on which the call is in progress. | |
418 | * @call: The call to query | |
419 | * | |
420 | * Get the call's peer RTT. | |
421 | */ | |
422 | u64 rxrpc_kernel_get_rtt(struct socket *sock, struct rxrpc_call *call) | |
423 | { | |
424 | return call->peer->rtt; | |
425 | } | |
426 | EXPORT_SYMBOL(rxrpc_kernel_get_rtt); |