12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later 2f66d7490SDavid Howells /* Peer event handling, typically ICMP messages. 38c3e34a4SDavid Howells * 48c3e34a4SDavid Howells * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. 58c3e34a4SDavid Howells * Written by David Howells (dhowells@redhat.com) 68c3e34a4SDavid Howells */ 78c3e34a4SDavid Howells 88c3e34a4SDavid Howells #include <linux/module.h> 98c3e34a4SDavid Howells #include <linux/net.h> 108c3e34a4SDavid Howells #include <linux/skbuff.h> 118c3e34a4SDavid Howells #include <linux/errqueue.h> 128c3e34a4SDavid Howells #include <linux/udp.h> 138c3e34a4SDavid Howells #include <linux/in.h> 148c3e34a4SDavid Howells #include <linux/in6.h> 158c3e34a4SDavid Howells #include <linux/icmp.h> 168c3e34a4SDavid Howells #include <net/sock.h> 178c3e34a4SDavid Howells #include <net/af_rxrpc.h> 188c3e34a4SDavid Howells #include <net/ip.h> 198c3e34a4SDavid Howells #include "ar-internal.h" 208c3e34a4SDavid Howells 21f66d7490SDavid Howells static void rxrpc_store_error(struct rxrpc_peer *, struct sock_exterr_skb *); 22f3344303SDavid Howells static void rxrpc_distribute_error(struct rxrpc_peer *, int, 23f3344303SDavid Howells enum rxrpc_call_completion); 24f66d7490SDavid Howells 258c3e34a4SDavid Howells /* 26ac56a0b4SDavid Howells * Find the peer associated with a local error. 27ac56a0b4SDavid Howells */ 28ac56a0b4SDavid Howells static struct rxrpc_peer *rxrpc_lookup_peer_local_rcu(struct rxrpc_local *local, 29494337c9SDavid Howells const struct sk_buff *skb, 30494337c9SDavid Howells struct sockaddr_rxrpc *srx) 31be6e6707SDavid Howells { 32be6e6707SDavid Howells struct sock_exterr_skb *serr = SKB_EXT_ERR(skb); 33be6e6707SDavid Howells 34be6e6707SDavid Howells _enter(""); 35be6e6707SDavid Howells 36494337c9SDavid Howells memset(srx, 0, sizeof(*srx)); 37494337c9SDavid Howells srx->transport_type = local->srx.transport_type; 38494337c9SDavid Howells srx->transport_len = local->srx.transport_len; 39494337c9SDavid Howells srx->transport.family = local->srx.transport.family; 40be6e6707SDavid Howells 41b6c66c43SDavid Howells /* Can we see an ICMP4 packet on an ICMP6 listening socket? and vice 42b6c66c43SDavid Howells * versa? 43b6c66c43SDavid Howells */ 44494337c9SDavid Howells switch (srx->transport.family) { 45be6e6707SDavid Howells case AF_INET: 4646894a13SDavid Howells srx->transport_len = sizeof(srx->transport.sin); 4746894a13SDavid Howells srx->transport.family = AF_INET; 48494337c9SDavid Howells srx->transport.sin.sin_port = serr->port; 49be6e6707SDavid Howells switch (serr->ee.ee_origin) { 50be6e6707SDavid Howells case SO_EE_ORIGIN_ICMP: 51494337c9SDavid Howells memcpy(&srx->transport.sin.sin_addr, 52be6e6707SDavid Howells skb_network_header(skb) + serr->addr_offset, 53be6e6707SDavid Howells sizeof(struct in_addr)); 54be6e6707SDavid Howells break; 55be6e6707SDavid Howells case SO_EE_ORIGIN_ICMP6: 56494337c9SDavid Howells memcpy(&srx->transport.sin.sin_addr, 57be6e6707SDavid Howells skb_network_header(skb) + serr->addr_offset + 12, 58be6e6707SDavid Howells sizeof(struct in_addr)); 59be6e6707SDavid Howells break; 60be6e6707SDavid Howells default: 61494337c9SDavid Howells memcpy(&srx->transport.sin.sin_addr, &ip_hdr(skb)->saddr, 62be6e6707SDavid Howells sizeof(struct in_addr)); 63be6e6707SDavid Howells break; 64be6e6707SDavid Howells } 65be6e6707SDavid Howells break; 66be6e6707SDavid Howells 67d1912747SDavid Howells #ifdef CONFIG_AF_RXRPC_IPV6 6875b54cb5SDavid Howells case AF_INET6: 6975b54cb5SDavid Howells switch (serr->ee.ee_origin) { 7075b54cb5SDavid Howells case SO_EE_ORIGIN_ICMP6: 7146894a13SDavid Howells srx->transport.sin6.sin6_port = serr->port; 72494337c9SDavid Howells memcpy(&srx->transport.sin6.sin6_addr, 7375b54cb5SDavid Howells skb_network_header(skb) + serr->addr_offset, 7475b54cb5SDavid Howells sizeof(struct in6_addr)); 7575b54cb5SDavid Howells break; 7675b54cb5SDavid Howells case SO_EE_ORIGIN_ICMP: 7746894a13SDavid Howells srx->transport_len = sizeof(srx->transport.sin); 7846894a13SDavid Howells srx->transport.family = AF_INET; 7946894a13SDavid Howells srx->transport.sin.sin_port = serr->port; 8046894a13SDavid Howells memcpy(&srx->transport.sin.sin_addr, 8175b54cb5SDavid Howells skb_network_header(skb) + serr->addr_offset, 8275b54cb5SDavid Howells sizeof(struct in_addr)); 8375b54cb5SDavid Howells break; 8475b54cb5SDavid Howells default: 85494337c9SDavid Howells memcpy(&srx->transport.sin6.sin6_addr, 8675b54cb5SDavid Howells &ipv6_hdr(skb)->saddr, 8775b54cb5SDavid Howells sizeof(struct in6_addr)); 8875b54cb5SDavid Howells break; 8975b54cb5SDavid Howells } 9075b54cb5SDavid Howells break; 91d1912747SDavid Howells #endif 9275b54cb5SDavid Howells 93be6e6707SDavid Howells default: 94be6e6707SDavid Howells BUG(); 95be6e6707SDavid Howells } 96be6e6707SDavid Howells 97494337c9SDavid Howells return rxrpc_lookup_peer_rcu(local, srx); 98be6e6707SDavid Howells } 99be6e6707SDavid Howells 100be6e6707SDavid Howells /* 1011a70c05bSDavid Howells * Handle an MTU/fragmentation problem. 1021a70c05bSDavid Howells */ 103ac56a0b4SDavid Howells static void rxrpc_adjust_mtu(struct rxrpc_peer *peer, unsigned int mtu) 1041a70c05bSDavid Howells { 1051a70c05bSDavid Howells /* wind down the local interface MTU */ 106e969c92cSDavid Howells if (mtu > 0 && peer->if_mtu == 65535 && mtu < peer->if_mtu) 1071a70c05bSDavid Howells peer->if_mtu = mtu; 1081a70c05bSDavid Howells 1091a70c05bSDavid Howells if (mtu == 0) { 1101a70c05bSDavid Howells /* they didn't give us a size, estimate one */ 1111a70c05bSDavid Howells mtu = peer->if_mtu; 1121a70c05bSDavid Howells if (mtu > 1500) { 1131a70c05bSDavid Howells mtu >>= 1; 1141a70c05bSDavid Howells if (mtu < 1500) 1151a70c05bSDavid Howells mtu = 1500; 1161a70c05bSDavid Howells } else { 1171a70c05bSDavid Howells mtu -= 100; 1181a70c05bSDavid Howells if (mtu < peer->hdrsize) 1191a70c05bSDavid Howells mtu = peer->hdrsize + 4; 1201a70c05bSDavid Howells } 1211a70c05bSDavid Howells } 1221a70c05bSDavid Howells 1231a70c05bSDavid Howells if (mtu < peer->mtu) { 1241a70c05bSDavid Howells spin_lock_bh(&peer->lock); 1251a70c05bSDavid Howells peer->mtu = mtu; 1261a70c05bSDavid Howells peer->maxdata = peer->mtu - peer->hdrsize; 1271a70c05bSDavid Howells spin_unlock_bh(&peer->lock); 1281a70c05bSDavid Howells } 1291a70c05bSDavid Howells } 1301a70c05bSDavid Howells 1311a70c05bSDavid Howells /* 132f66d7490SDavid Howells * Handle an error received on the local endpoint. 1338c3e34a4SDavid Howells */ 134abe89ef0SDavid Howells void rxrpc_error_report(struct sock *sk) 1358c3e34a4SDavid Howells { 1368c3e34a4SDavid Howells struct sock_exterr_skb *serr; 137494337c9SDavid Howells struct sockaddr_rxrpc srx; 1382ca4f6caSEric Dumazet struct rxrpc_local *local; 139ac56a0b4SDavid Howells struct rxrpc_peer *peer = NULL; 1408c3e34a4SDavid Howells struct sk_buff *skb; 1418c3e34a4SDavid Howells 1422ca4f6caSEric Dumazet rcu_read_lock(); 1432ca4f6caSEric Dumazet local = rcu_dereference_sk_user_data(sk); 1442ca4f6caSEric Dumazet if (unlikely(!local)) { 1452ca4f6caSEric Dumazet rcu_read_unlock(); 146f0308fb0SDavid Howells return; 1472ca4f6caSEric Dumazet } 1488c3e34a4SDavid Howells _enter("%p{%d}", sk, local->debug_id); 1498c3e34a4SDavid Howells 15056d282d9SMarc Dionne /* Clear the outstanding error value on the socket so that it doesn't 15156d282d9SMarc Dionne * cause kernel_sendmsg() to return it later. 15256d282d9SMarc Dionne */ 15356d282d9SMarc Dionne sock_error(sk); 15456d282d9SMarc Dionne 1558c3e34a4SDavid Howells skb = sock_dequeue_err_skb(sk); 1568c3e34a4SDavid Howells if (!skb) { 1572ca4f6caSEric Dumazet rcu_read_unlock(); 1588c3e34a4SDavid Howells _leave("UDP socket errqueue empty"); 1598c3e34a4SDavid Howells return; 1608c3e34a4SDavid Howells } 161987db9f7SDavid Howells rxrpc_new_skb(skb, rxrpc_skb_received); 1628c3e34a4SDavid Howells serr = SKB_EXT_ERR(skb); 163b6c66c43SDavid Howells if (!skb->len && serr->ee.ee_origin == SO_EE_ORIGIN_TIMESTAMPING) { 164b6c66c43SDavid Howells _leave("UDP empty message"); 165b6c66c43SDavid Howells rcu_read_unlock(); 166b6c66c43SDavid Howells rxrpc_free_skb(skb, rxrpc_skb_freed); 167b6c66c43SDavid Howells return; 168b6c66c43SDavid Howells } 1698c3e34a4SDavid Howells 170ac56a0b4SDavid Howells peer = rxrpc_lookup_peer_local_rcu(local, skb, &srx); 171be6e6707SDavid Howells if (peer && !rxrpc_get_peer_maybe(peer)) 172be6e6707SDavid Howells peer = NULL; 173b6c66c43SDavid Howells if (!peer) { 174b6c66c43SDavid Howells rcu_read_unlock(); 175b6c66c43SDavid Howells rxrpc_free_skb(skb, rxrpc_skb_freed); 176b6c66c43SDavid Howells _leave(" [no peer]"); 177b6c66c43SDavid Howells return; 1781a70c05bSDavid Howells } 179f66d7490SDavid Howells 180b6c66c43SDavid Howells trace_rxrpc_rx_icmp(peer, &serr->ee, &srx); 181b6c66c43SDavid Howells 182b6c66c43SDavid Howells if ((serr->ee.ee_origin == SO_EE_ORIGIN_ICMP && 183b6c66c43SDavid Howells serr->ee.ee_type == ICMP_DEST_UNREACH && 184b6c66c43SDavid Howells serr->ee.ee_code == ICMP_FRAG_NEEDED)) { 185b6c66c43SDavid Howells rxrpc_adjust_mtu(peer, serr->ee.ee_info); 186b6c66c43SDavid Howells goto out; 187b6c66c43SDavid Howells } 188b6c66c43SDavid Howells 189b6c66c43SDavid Howells rxrpc_store_error(peer, serr); 190b6c66c43SDavid Howells out: 191f66d7490SDavid Howells rcu_read_unlock(); 192987db9f7SDavid Howells rxrpc_free_skb(skb, rxrpc_skb_freed); 1931890fea7SDavid Howells rxrpc_put_peer(peer); 194b6c66c43SDavid Howells 1958c3e34a4SDavid Howells _leave(""); 1968c3e34a4SDavid Howells } 1978c3e34a4SDavid Howells 1988c3e34a4SDavid Howells /* 199f66d7490SDavid Howells * Map an error report to error codes on the peer record. 2008c3e34a4SDavid Howells */ 201f66d7490SDavid Howells static void rxrpc_store_error(struct rxrpc_peer *peer, 202f66d7490SDavid Howells struct sock_exterr_skb *serr) 2038c3e34a4SDavid Howells { 204f3344303SDavid Howells enum rxrpc_call_completion compl = RXRPC_CALL_NETWORK_ERROR; 2058c3e34a4SDavid Howells struct sock_extended_err *ee; 2068c3e34a4SDavid Howells int err; 2078c3e34a4SDavid Howells 2088c3e34a4SDavid Howells _enter(""); 2098c3e34a4SDavid Howells 2108c3e34a4SDavid Howells ee = &serr->ee; 2118c3e34a4SDavid Howells 2128c3e34a4SDavid Howells err = ee->ee_errno; 2138c3e34a4SDavid Howells 2148c3e34a4SDavid Howells switch (ee->ee_origin) { 215f66d7490SDavid Howells case SO_EE_ORIGIN_NONE: 2168c3e34a4SDavid Howells case SO_EE_ORIGIN_LOCAL: 217f3344303SDavid Howells compl = RXRPC_CALL_LOCAL_ERROR; 2188c3e34a4SDavid Howells break; 2198c3e34a4SDavid Howells 2208c3e34a4SDavid Howells case SO_EE_ORIGIN_ICMP6: 22123e2db31SDavid Howells if (err == EACCES) 22223e2db31SDavid Howells err = EHOSTUNREACH; 223df561f66SGustavo A. R. Silva fallthrough; 224e969c92cSDavid Howells case SO_EE_ORIGIN_ICMP: 2258c3e34a4SDavid Howells default: 2268c3e34a4SDavid Howells break; 2278c3e34a4SDavid Howells } 2288c3e34a4SDavid Howells 229f3344303SDavid Howells rxrpc_distribute_error(peer, err, compl); 230f66d7490SDavid Howells } 2318c3e34a4SDavid Howells 232f66d7490SDavid Howells /* 233f3344303SDavid Howells * Distribute an error that occurred on a peer. 234f66d7490SDavid Howells */ 235f3344303SDavid Howells static void rxrpc_distribute_error(struct rxrpc_peer *peer, int error, 236f3344303SDavid Howells enum rxrpc_call_completion compl) 237f66d7490SDavid Howells { 238f66d7490SDavid Howells struct rxrpc_call *call; 2398c3e34a4SDavid Howells 240f3344303SDavid Howells hlist_for_each_entry_rcu(call, &peer->error_targets, error_link) { 241e34d4234SDavid Howells rxrpc_see_call(call); 2425ac0d622SDavid Howells rxrpc_set_call_completion(call, compl, 0, -error); 2438c3e34a4SDavid Howells } 2448c3e34a4SDavid Howells } 245cf1a6474SDavid Howells 246cf1a6474SDavid Howells /* 247330bdcfaSDavid Howells * Perform keep-alive pings. 248330bdcfaSDavid Howells */ 249330bdcfaSDavid Howells static void rxrpc_peer_keepalive_dispatch(struct rxrpc_net *rxnet, 250330bdcfaSDavid Howells struct list_head *collector, 251330bdcfaSDavid Howells time64_t base, 252330bdcfaSDavid Howells u8 cursor) 253330bdcfaSDavid Howells { 254330bdcfaSDavid Howells struct rxrpc_peer *peer; 255330bdcfaSDavid Howells const u8 mask = ARRAY_SIZE(rxnet->peer_keepalive) - 1; 256330bdcfaSDavid Howells time64_t keepalive_at; 257330bdcfaSDavid Howells int slot; 258330bdcfaSDavid Howells 259330bdcfaSDavid Howells spin_lock_bh(&rxnet->peer_hash_lock); 260330bdcfaSDavid Howells 261330bdcfaSDavid Howells while (!list_empty(collector)) { 262330bdcfaSDavid Howells peer = list_entry(collector->next, 263330bdcfaSDavid Howells struct rxrpc_peer, keepalive_link); 264330bdcfaSDavid Howells 265330bdcfaSDavid Howells list_del_init(&peer->keepalive_link); 266330bdcfaSDavid Howells if (!rxrpc_get_peer_maybe(peer)) 267330bdcfaSDavid Howells continue; 268330bdcfaSDavid Howells 269*0fde882fSDavid Howells if (__rxrpc_use_local(peer->local, rxrpc_local_use_peer_keepalive)) { 270330bdcfaSDavid Howells spin_unlock_bh(&rxnet->peer_hash_lock); 271330bdcfaSDavid Howells 272330bdcfaSDavid Howells keepalive_at = peer->last_tx_at + RXRPC_KEEPALIVE_TIME; 273330bdcfaSDavid Howells slot = keepalive_at - base; 274330bdcfaSDavid Howells _debug("%02x peer %u t=%d {%pISp}", 275330bdcfaSDavid Howells cursor, peer->debug_id, slot, &peer->srx.transport); 276330bdcfaSDavid Howells 277330bdcfaSDavid Howells if (keepalive_at <= base || 278330bdcfaSDavid Howells keepalive_at > base + RXRPC_KEEPALIVE_TIME) { 279330bdcfaSDavid Howells rxrpc_send_keepalive(peer); 280330bdcfaSDavid Howells slot = RXRPC_KEEPALIVE_TIME; 281330bdcfaSDavid Howells } 282330bdcfaSDavid Howells 28304d36d74SDavid Howells /* A transmission to this peer occurred since last we 28404d36d74SDavid Howells * examined it so put it into the appropriate future 28504d36d74SDavid Howells * bucket. 286330bdcfaSDavid Howells */ 287330bdcfaSDavid Howells slot += cursor; 288330bdcfaSDavid Howells slot &= mask; 289330bdcfaSDavid Howells spin_lock_bh(&rxnet->peer_hash_lock); 290330bdcfaSDavid Howells list_add_tail(&peer->keepalive_link, 291330bdcfaSDavid Howells &rxnet->peer_keepalive[slot & mask]); 292*0fde882fSDavid Howells rxrpc_unuse_local(peer->local, rxrpc_local_unuse_peer_keepalive); 29304d36d74SDavid Howells } 29460034d3dSDavid Howells rxrpc_put_peer_locked(peer); 295330bdcfaSDavid Howells } 296330bdcfaSDavid Howells 297330bdcfaSDavid Howells spin_unlock_bh(&rxnet->peer_hash_lock); 298330bdcfaSDavid Howells } 299330bdcfaSDavid Howells 300330bdcfaSDavid Howells /* 301ace45becSDavid Howells * Perform keep-alive pings with VERSION packets to keep any NAT alive. 302ace45becSDavid Howells */ 303ace45becSDavid Howells void rxrpc_peer_keepalive_worker(struct work_struct *work) 304ace45becSDavid Howells { 305ace45becSDavid Howells struct rxrpc_net *rxnet = 306ace45becSDavid Howells container_of(work, struct rxrpc_net, peer_keepalive_work); 307330bdcfaSDavid Howells const u8 mask = ARRAY_SIZE(rxnet->peer_keepalive) - 1; 308330bdcfaSDavid Howells time64_t base, now, delay; 309330bdcfaSDavid Howells u8 cursor, stop; 310330bdcfaSDavid Howells LIST_HEAD(collector); 311ace45becSDavid Howells 312330bdcfaSDavid Howells now = ktime_get_seconds(); 313ace45becSDavid Howells base = rxnet->peer_keepalive_base; 314ace45becSDavid Howells cursor = rxnet->peer_keepalive_cursor; 315330bdcfaSDavid Howells _enter("%lld,%u", base - now, cursor); 316ace45becSDavid Howells 317330bdcfaSDavid Howells if (!rxnet->live) 318330bdcfaSDavid Howells return; 319ace45becSDavid Howells 320330bdcfaSDavid Howells /* Remove to a temporary list all the peers that are currently lodged 321330bdcfaSDavid Howells * in expired buckets plus all new peers. 322330bdcfaSDavid Howells * 323330bdcfaSDavid Howells * Everything in the bucket at the cursor is processed this 324330bdcfaSDavid Howells * second; the bucket at cursor + 1 goes at now + 1s and so 325330bdcfaSDavid Howells * on... 326ace45becSDavid Howells */ 327ace45becSDavid Howells spin_lock_bh(&rxnet->peer_hash_lock); 328330bdcfaSDavid Howells list_splice_init(&rxnet->peer_keepalive_new, &collector); 329ace45becSDavid Howells 330330bdcfaSDavid Howells stop = cursor + ARRAY_SIZE(rxnet->peer_keepalive); 331330bdcfaSDavid Howells while (base <= now && (s8)(cursor - stop) < 0) { 332330bdcfaSDavid Howells list_splice_tail_init(&rxnet->peer_keepalive[cursor & mask], 333330bdcfaSDavid Howells &collector); 334330bdcfaSDavid Howells base++; 335ace45becSDavid Howells cursor++; 336330bdcfaSDavid Howells } 337ace45becSDavid Howells 338330bdcfaSDavid Howells base = now; 339330bdcfaSDavid Howells spin_unlock_bh(&rxnet->peer_hash_lock); 340330bdcfaSDavid Howells 341ace45becSDavid Howells rxnet->peer_keepalive_base = base; 342ace45becSDavid Howells rxnet->peer_keepalive_cursor = cursor; 343330bdcfaSDavid Howells rxrpc_peer_keepalive_dispatch(rxnet, &collector, base, cursor); 344330bdcfaSDavid Howells ASSERT(list_empty(&collector)); 345330bdcfaSDavid Howells 346330bdcfaSDavid Howells /* Schedule the timer for the next occupied timeslot. */ 347330bdcfaSDavid Howells cursor = rxnet->peer_keepalive_cursor; 348330bdcfaSDavid Howells stop = cursor + RXRPC_KEEPALIVE_TIME - 1; 349330bdcfaSDavid Howells for (; (s8)(cursor - stop) < 0; cursor++) { 350330bdcfaSDavid Howells if (!list_empty(&rxnet->peer_keepalive[cursor & mask])) 351330bdcfaSDavid Howells break; 352330bdcfaSDavid Howells base++; 353330bdcfaSDavid Howells } 354330bdcfaSDavid Howells 355330bdcfaSDavid Howells now = ktime_get_seconds(); 356330bdcfaSDavid Howells delay = base - now; 357330bdcfaSDavid Howells if (delay < 1) 358330bdcfaSDavid Howells delay = 1; 359330bdcfaSDavid Howells delay *= HZ; 360330bdcfaSDavid Howells if (rxnet->live) 361ace45becSDavid Howells timer_reduce(&rxnet->peer_keepalive_timer, jiffies + delay); 362330bdcfaSDavid Howells 363ace45becSDavid Howells _leave(""); 364ace45becSDavid Howells } 365