1// SPDX-License-Identifier: GPL-2.0-or-later 2/* RxRPC packet transmission 3 * 4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 10#include <linux/net.h> 11#include <linux/gfp.h> 12#include <linux/skbuff.h> 13#include <linux/export.h> 14#include <net/sock.h> 15#include <net/af_rxrpc.h> 16#include "ar-internal.h" 17 18struct rxrpc_ack_buffer { 19 struct rxrpc_wire_header whdr; 20 struct rxrpc_ackpacket ack; 21 u8 acks[255]; 22 u8 pad[3]; 23 struct rxrpc_ackinfo ackinfo; 24}; 25 26struct rxrpc_abort_buffer { 27 struct rxrpc_wire_header whdr; 28 __be32 abort_code; 29}; 30 31static const char rxrpc_keepalive_string[] = ""; 32 33/* 34 * Increase Tx backoff on transmission failure and clear it on success. 35 */ 36static void rxrpc_tx_backoff(struct rxrpc_call *call, int ret) 37{ 38 if (ret < 0) { 39 u16 tx_backoff = READ_ONCE(call->tx_backoff); 40 41 if (tx_backoff < HZ) 42 WRITE_ONCE(call->tx_backoff, tx_backoff + 1); 43 } else { 44 WRITE_ONCE(call->tx_backoff, 0); 45 } 46} 47 48/* 49 * Arrange for a keepalive ping a certain time after we last transmitted. This 50 * lets the far side know we're still interested in this call and helps keep 51 * the route through any intervening firewall open. 52 * 53 * Receiving a response to the ping will prevent the ->expect_rx_by timer from 54 * expiring. 55 */ 56static void rxrpc_set_keepalive(struct rxrpc_call *call) 57{ 58 unsigned long now = jiffies, keepalive_at = call->next_rx_timo / 6; 59 60 keepalive_at += now; 61 WRITE_ONCE(call->keepalive_at, keepalive_at); 62 rxrpc_reduce_call_timer(call, keepalive_at, now, 63 rxrpc_timer_set_for_keepalive); 64} 65 66/* 67 * Fill out an ACK packet. 68 */ 69static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn, 70 struct rxrpc_call *call, 71 struct rxrpc_ack_buffer *pkt, 72 rxrpc_seq_t *_hard_ack, 73 rxrpc_seq_t *_top, 74 u8 reason) 75{ 76 rxrpc_serial_t serial; 77 unsigned int tmp; 78 rxrpc_seq_t hard_ack, top, seq; 79 int ix; 80 u32 mtu, jmax; 81 u8 *ackp = pkt->acks; 82 83 tmp = atomic_xchg(&call->ackr_nr_unacked, 0); 84 tmp |= atomic_xchg(&call->ackr_nr_consumed, 0); 85 if (!tmp && (reason == RXRPC_ACK_DELAY || 86 reason == RXRPC_ACK_IDLE)) 87 return 0; 88 89 /* Barrier against rxrpc_input_data(). */ 90 serial = call->ackr_serial; 91 hard_ack = READ_ONCE(call->rx_hard_ack); 92 top = smp_load_acquire(&call->rx_top); 93 *_hard_ack = hard_ack; 94 *_top = top; 95 96 pkt->ack.bufferSpace = htons(0); 97 pkt->ack.maxSkew = htons(0); 98 pkt->ack.firstPacket = htonl(hard_ack + 1); 99 pkt->ack.previousPacket = htonl(call->ackr_highest_seq); 100 pkt->ack.serial = htonl(serial); 101 pkt->ack.reason = reason; 102 pkt->ack.nAcks = top - hard_ack; 103 104 if (reason == RXRPC_ACK_PING) 105 pkt->whdr.flags |= RXRPC_REQUEST_ACK; 106 107 if (after(top, hard_ack)) { 108 seq = hard_ack + 1; 109 do { 110 ix = seq & RXRPC_RXTX_BUFF_MASK; 111 if (call->rxtx_buffer[ix]) 112 *ackp++ = RXRPC_ACK_TYPE_ACK; 113 else 114 *ackp++ = RXRPC_ACK_TYPE_NACK; 115 seq++; 116 } while (before_eq(seq, top)); 117 } 118 119 mtu = conn->params.peer->if_mtu; 120 mtu -= conn->params.peer->hdrsize; 121 jmax = (call->nr_jumbo_bad > 3) ? 1 : rxrpc_rx_jumbo_max; 122 pkt->ackinfo.rxMTU = htonl(rxrpc_rx_mtu); 123 pkt->ackinfo.maxMTU = htonl(mtu); 124 pkt->ackinfo.rwind = htonl(call->rx_winsize); 125 pkt->ackinfo.jumbo_max = htonl(jmax); 126 127 *ackp++ = 0; 128 *ackp++ = 0; 129 *ackp++ = 0; 130 return top - hard_ack + 3; 131} 132 133/* 134 * Record the beginning of an RTT probe. 135 */ 136static int rxrpc_begin_rtt_probe(struct rxrpc_call *call, rxrpc_serial_t serial, 137 enum rxrpc_rtt_tx_trace why) 138{ 139 unsigned long avail = call->rtt_avail; 140 int rtt_slot = 9; 141 142 if (!(avail & RXRPC_CALL_RTT_AVAIL_MASK)) 143 goto no_slot; 144 145 rtt_slot = __ffs(avail & RXRPC_CALL_RTT_AVAIL_MASK); 146 if (!test_and_clear_bit(rtt_slot, &call->rtt_avail)) 147 goto no_slot; 148 149 call->rtt_serial[rtt_slot] = serial; 150 call->rtt_sent_at[rtt_slot] = ktime_get_real(); 151 smp_wmb(); /* Write data before avail bit */ 152 set_bit(rtt_slot + RXRPC_CALL_RTT_PEND_SHIFT, &call->rtt_avail); 153 154 trace_rxrpc_rtt_tx(call, why, rtt_slot, serial); 155 return rtt_slot; 156 157no_slot: 158 trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_no_slot, rtt_slot, serial); 159 return -1; 160} 161 162/* 163 * Cancel an RTT probe. 164 */ 165static void rxrpc_cancel_rtt_probe(struct rxrpc_call *call, 166 rxrpc_serial_t serial, int rtt_slot) 167{ 168 if (rtt_slot != -1) { 169 clear_bit(rtt_slot + RXRPC_CALL_RTT_PEND_SHIFT, &call->rtt_avail); 170 smp_wmb(); /* Clear pending bit before setting slot */ 171 set_bit(rtt_slot, &call->rtt_avail); 172 trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_cancel, rtt_slot, serial); 173 } 174} 175 176/* 177 * Send an ACK call packet. 178 */ 179int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping, 180 rxrpc_serial_t *_serial) 181{ 182 struct rxrpc_connection *conn; 183 struct rxrpc_ack_buffer *pkt; 184 struct msghdr msg; 185 struct kvec iov[2]; 186 rxrpc_serial_t serial; 187 rxrpc_seq_t hard_ack, top; 188 size_t len, n; 189 int ret, rtt_slot = -1; 190 u8 reason; 191 192 if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) 193 return -ECONNRESET; 194 195 pkt = kzalloc(sizeof(*pkt), GFP_KERNEL); 196 if (!pkt) 197 return -ENOMEM; 198 199 conn = call->conn; 200 201 msg.msg_name = &call->peer->srx.transport; 202 msg.msg_namelen = call->peer->srx.transport_len; 203 msg.msg_control = NULL; 204 msg.msg_controllen = 0; 205 msg.msg_flags = 0; 206 207 pkt->whdr.epoch = htonl(conn->proto.epoch); 208 pkt->whdr.cid = htonl(call->cid); 209 pkt->whdr.callNumber = htonl(call->call_id); 210 pkt->whdr.seq = 0; 211 pkt->whdr.type = RXRPC_PACKET_TYPE_ACK; 212 pkt->whdr.flags = RXRPC_SLOW_START_OK | conn->out_clientflag; 213 pkt->whdr.userStatus = 0; 214 pkt->whdr.securityIndex = call->security_ix; 215 pkt->whdr._rsvd = 0; 216 pkt->whdr.serviceId = htons(call->service_id); 217 218 spin_lock_bh(&call->lock); 219 if (ping) { 220 reason = RXRPC_ACK_PING; 221 } else { 222 reason = call->ackr_reason; 223 if (!call->ackr_reason) { 224 spin_unlock_bh(&call->lock); 225 ret = 0; 226 goto out; 227 } 228 call->ackr_reason = 0; 229 } 230 n = rxrpc_fill_out_ack(conn, call, pkt, &hard_ack, &top, reason); 231 232 spin_unlock_bh(&call->lock); 233 if (n == 0) { 234 kfree(pkt); 235 return 0; 236 } 237 238 iov[0].iov_base = pkt; 239 iov[0].iov_len = sizeof(pkt->whdr) + sizeof(pkt->ack) + n; 240 iov[1].iov_base = &pkt->ackinfo; 241 iov[1].iov_len = sizeof(pkt->ackinfo); 242 len = iov[0].iov_len + iov[1].iov_len; 243 244 serial = atomic_inc_return(&conn->serial); 245 pkt->whdr.serial = htonl(serial); 246 trace_rxrpc_tx_ack(call->debug_id, serial, 247 ntohl(pkt->ack.firstPacket), 248 ntohl(pkt->ack.serial), 249 pkt->ack.reason, pkt->ack.nAcks); 250 if (_serial) 251 *_serial = serial; 252 253 if (ping) 254 rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_ping); 255 256 ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len); 257 conn->params.peer->last_tx_at = ktime_get_seconds(); 258 if (ret < 0) 259 trace_rxrpc_tx_fail(call->debug_id, serial, ret, 260 rxrpc_tx_point_call_ack); 261 else 262 trace_rxrpc_tx_packet(call->debug_id, &pkt->whdr, 263 rxrpc_tx_point_call_ack); 264 rxrpc_tx_backoff(call, ret); 265 266 if (call->state < RXRPC_CALL_COMPLETE) { 267 if (ret < 0) { 268 rxrpc_cancel_rtt_probe(call, serial, rtt_slot); 269 rxrpc_propose_ACK(call, pkt->ack.reason, 270 ntohl(pkt->ack.serial), 271 false, true, 272 rxrpc_propose_ack_retry_tx); 273 } 274 275 rxrpc_set_keepalive(call); 276 } 277 278out: 279 kfree(pkt); 280 return ret; 281} 282 283/* 284 * Send an ABORT call packet. 285 */ 286int rxrpc_send_abort_packet(struct rxrpc_call *call) 287{ 288 struct rxrpc_connection *conn; 289 struct rxrpc_abort_buffer pkt; 290 struct msghdr msg; 291 struct kvec iov[1]; 292 rxrpc_serial_t serial; 293 int ret; 294 295 /* Don't bother sending aborts for a client call once the server has 296 * hard-ACK'd all of its request data. After that point, we're not 297 * going to stop the operation proceeding, and whilst we might limit 298 * the reply, it's not worth it if we can send a new call on the same 299 * channel instead, thereby closing off this call. 300 */ 301 if (rxrpc_is_client_call(call) && 302 test_bit(RXRPC_CALL_TX_LAST, &call->flags)) 303 return 0; 304 305 if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) 306 return -ECONNRESET; 307 308 conn = call->conn; 309 310 msg.msg_name = &call->peer->srx.transport; 311 msg.msg_namelen = call->peer->srx.transport_len; 312 msg.msg_control = NULL; 313 msg.msg_controllen = 0; 314 msg.msg_flags = 0; 315 316 pkt.whdr.epoch = htonl(conn->proto.epoch); 317 pkt.whdr.cid = htonl(call->cid); 318 pkt.whdr.callNumber = htonl(call->call_id); 319 pkt.whdr.seq = 0; 320 pkt.whdr.type = RXRPC_PACKET_TYPE_ABORT; 321 pkt.whdr.flags = conn->out_clientflag; 322 pkt.whdr.userStatus = 0; 323 pkt.whdr.securityIndex = call->security_ix; 324 pkt.whdr._rsvd = 0; 325 pkt.whdr.serviceId = htons(call->service_id); 326 pkt.abort_code = htonl(call->abort_code); 327 328 iov[0].iov_base = &pkt; 329 iov[0].iov_len = sizeof(pkt); 330 331 serial = atomic_inc_return(&conn->serial); 332 pkt.whdr.serial = htonl(serial); 333 334 ret = kernel_sendmsg(conn->params.local->socket, 335 &msg, iov, 1, sizeof(pkt)); 336 conn->params.peer->last_tx_at = ktime_get_seconds(); 337 if (ret < 0) 338 trace_rxrpc_tx_fail(call->debug_id, serial, ret, 339 rxrpc_tx_point_call_abort); 340 else 341 trace_rxrpc_tx_packet(call->debug_id, &pkt.whdr, 342 rxrpc_tx_point_call_abort); 343 rxrpc_tx_backoff(call, ret); 344 return ret; 345} 346 347/* 348 * send a packet through the transport endpoint 349 */ 350int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb, 351 bool retrans) 352{ 353 struct rxrpc_connection *conn = call->conn; 354 struct rxrpc_wire_header whdr; 355 struct rxrpc_skb_priv *sp = rxrpc_skb(skb); 356 struct msghdr msg; 357 struct kvec iov[2]; 358 rxrpc_serial_t serial; 359 size_t len; 360 int ret, rtt_slot = -1; 361 362 _enter(",{%d}", skb->len); 363 364 if (hlist_unhashed(&call->error_link)) { 365 spin_lock_bh(&call->peer->lock); 366 hlist_add_head_rcu(&call->error_link, &call->peer->error_targets); 367 spin_unlock_bh(&call->peer->lock); 368 } 369 370 /* Each transmission of a Tx packet needs a new serial number */ 371 serial = atomic_inc_return(&conn->serial); 372 373 whdr.epoch = htonl(conn->proto.epoch); 374 whdr.cid = htonl(call->cid); 375 whdr.callNumber = htonl(call->call_id); 376 whdr.seq = htonl(sp->hdr.seq); 377 whdr.serial = htonl(serial); 378 whdr.type = RXRPC_PACKET_TYPE_DATA; 379 whdr.flags = sp->hdr.flags; 380 whdr.userStatus = 0; 381 whdr.securityIndex = call->security_ix; 382 whdr._rsvd = htons(sp->hdr._rsvd); 383 whdr.serviceId = htons(call->service_id); 384 385 if (test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) && 386 sp->hdr.seq == 1) 387 whdr.userStatus = RXRPC_USERSTATUS_SERVICE_UPGRADE; 388 389 iov[0].iov_base = &whdr; 390 iov[0].iov_len = sizeof(whdr); 391 iov[1].iov_base = skb->head; 392 iov[1].iov_len = skb->len; 393 len = iov[0].iov_len + iov[1].iov_len; 394 395 msg.msg_name = &call->peer->srx.transport; 396 msg.msg_namelen = call->peer->srx.transport_len; 397 msg.msg_control = NULL; 398 msg.msg_controllen = 0; 399 msg.msg_flags = 0; 400 401 /* If our RTT cache needs working on, request an ACK. Also request 402 * ACKs if a DATA packet appears to have been lost. 403 * 404 * However, we mustn't request an ACK on the last reply packet of a 405 * service call, lest OpenAFS incorrectly send us an ACK with some 406 * soft-ACKs in it and then never follow up with a proper hard ACK. 407 */ 408 if ((!(sp->hdr.flags & RXRPC_LAST_PACKET) || 409 rxrpc_to_server(sp) 410 ) && 411 (test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events) || 412 retrans || 413 call->cong_mode == RXRPC_CALL_SLOW_START || 414 (call->peer->rtt_count < 3 && sp->hdr.seq & 1) || 415 ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), 416 ktime_get_real()))) 417 whdr.flags |= RXRPC_REQUEST_ACK; 418 419 if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) { 420 static int lose; 421 if ((lose++ & 7) == 7) { 422 ret = 0; 423 trace_rxrpc_tx_data(call, sp->hdr.seq, serial, 424 whdr.flags, retrans, true); 425 goto done; 426 } 427 } 428 429 trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags, retrans, 430 false); 431 432 /* send the packet with the don't fragment bit set if we currently 433 * think it's small enough */ 434 if (iov[1].iov_len >= call->peer->maxdata) 435 goto send_fragmentable; 436 437 down_read(&conn->params.local->defrag_sem); 438 439 sp->hdr.serial = serial; 440 smp_wmb(); /* Set serial before timestamp */ 441 skb->tstamp = ktime_get_real(); 442 if (whdr.flags & RXRPC_REQUEST_ACK) 443 rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_data); 444 445 /* send the packet by UDP 446 * - returns -EMSGSIZE if UDP would have to fragment the packet 447 * to go out of the interface 448 * - in which case, we'll have processed the ICMP error 449 * message and update the peer record 450 */ 451 ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len); 452 conn->params.peer->last_tx_at = ktime_get_seconds(); 453 454 up_read(&conn->params.local->defrag_sem); 455 if (ret < 0) { 456 rxrpc_cancel_rtt_probe(call, serial, rtt_slot); 457 trace_rxrpc_tx_fail(call->debug_id, serial, ret, 458 rxrpc_tx_point_call_data_nofrag); 459 } else { 460 trace_rxrpc_tx_packet(call->debug_id, &whdr, 461 rxrpc_tx_point_call_data_nofrag); 462 } 463 464 rxrpc_tx_backoff(call, ret); 465 if (ret == -EMSGSIZE) 466 goto send_fragmentable; 467 468done: 469 if (ret >= 0) { 470 if (whdr.flags & RXRPC_REQUEST_ACK) { 471 call->peer->rtt_last_req = skb->tstamp; 472 if (call->peer->rtt_count > 1) { 473 unsigned long nowj = jiffies, ack_lost_at; 474 475 ack_lost_at = rxrpc_get_rto_backoff(call->peer, false); 476 ack_lost_at += nowj; 477 WRITE_ONCE(call->ack_lost_at, ack_lost_at); 478 rxrpc_reduce_call_timer(call, ack_lost_at, nowj, 479 rxrpc_timer_set_for_lost_ack); 480 } 481 } 482 483 if (sp->hdr.seq == 1 && 484 !test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER, 485 &call->flags)) { 486 unsigned long nowj = jiffies, expect_rx_by; 487 488 expect_rx_by = nowj + call->next_rx_timo; 489 WRITE_ONCE(call->expect_rx_by, expect_rx_by); 490 rxrpc_reduce_call_timer(call, expect_rx_by, nowj, 491 rxrpc_timer_set_for_normal); 492 } 493 494 rxrpc_set_keepalive(call); 495 } else { 496 /* Cancel the call if the initial transmission fails, 497 * particularly if that's due to network routing issues that 498 * aren't going away anytime soon. The layer above can arrange 499 * the retransmission. 500 */ 501 if (!test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER, &call->flags)) 502 rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 503 RX_USER_ABORT, ret); 504 } 505 506 _leave(" = %d [%u]", ret, call->peer->maxdata); 507 return ret; 508 509send_fragmentable: 510 /* attempt to send this message with fragmentation enabled */ 511 _debug("send fragment"); 512 513 down_write(&conn->params.local->defrag_sem); 514 515 sp->hdr.serial = serial; 516 smp_wmb(); /* Set serial before timestamp */ 517 skb->tstamp = ktime_get_real(); 518 if (whdr.flags & RXRPC_REQUEST_ACK) 519 rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_data); 520 521 switch (conn->params.local->srx.transport.family) { 522 case AF_INET6: 523 case AF_INET: 524 ip_sock_set_mtu_discover(conn->params.local->socket->sk, 525 IP_PMTUDISC_DONT); 526 ret = kernel_sendmsg(conn->params.local->socket, &msg, 527 iov, 2, len); 528 conn->params.peer->last_tx_at = ktime_get_seconds(); 529 530 ip_sock_set_mtu_discover(conn->params.local->socket->sk, 531 IP_PMTUDISC_DO); 532 break; 533 534 default: 535 BUG(); 536 } 537 538 if (ret < 0) { 539 rxrpc_cancel_rtt_probe(call, serial, rtt_slot); 540 trace_rxrpc_tx_fail(call->debug_id, serial, ret, 541 rxrpc_tx_point_call_data_frag); 542 } else { 543 trace_rxrpc_tx_packet(call->debug_id, &whdr, 544 rxrpc_tx_point_call_data_frag); 545 } 546 rxrpc_tx_backoff(call, ret); 547 548 up_write(&conn->params.local->defrag_sem); 549 goto done; 550} 551 552/* 553 * reject packets through the local endpoint 554 */ 555void rxrpc_reject_packets(struct rxrpc_local *local) 556{ 557 struct sockaddr_rxrpc srx; 558 struct rxrpc_skb_priv *sp; 559 struct rxrpc_wire_header whdr; 560 struct sk_buff *skb; 561 struct msghdr msg; 562 struct kvec iov[2]; 563 size_t size; 564 __be32 code; 565 int ret, ioc; 566 567 _enter("%d", local->debug_id); 568 569 iov[0].iov_base = &whdr; 570 iov[0].iov_len = sizeof(whdr); 571 iov[1].iov_base = &code; 572 iov[1].iov_len = sizeof(code); 573 574 msg.msg_name = &srx.transport; 575 msg.msg_control = NULL; 576 msg.msg_controllen = 0; 577 msg.msg_flags = 0; 578 579 memset(&whdr, 0, sizeof(whdr)); 580 581 while ((skb = skb_dequeue(&local->reject_queue))) { 582 rxrpc_see_skb(skb, rxrpc_skb_seen); 583 sp = rxrpc_skb(skb); 584 585 switch (skb->mark) { 586 case RXRPC_SKB_MARK_REJECT_BUSY: 587 whdr.type = RXRPC_PACKET_TYPE_BUSY; 588 size = sizeof(whdr); 589 ioc = 1; 590 break; 591 case RXRPC_SKB_MARK_REJECT_ABORT: 592 whdr.type = RXRPC_PACKET_TYPE_ABORT; 593 code = htonl(skb->priority); 594 size = sizeof(whdr) + sizeof(code); 595 ioc = 2; 596 break; 597 default: 598 rxrpc_free_skb(skb, rxrpc_skb_freed); 599 continue; 600 } 601 602 if (rxrpc_extract_addr_from_skb(&srx, skb) == 0) { 603 msg.msg_namelen = srx.transport_len; 604 605 whdr.epoch = htonl(sp->hdr.epoch); 606 whdr.cid = htonl(sp->hdr.cid); 607 whdr.callNumber = htonl(sp->hdr.callNumber); 608 whdr.serviceId = htons(sp->hdr.serviceId); 609 whdr.flags = sp->hdr.flags; 610 whdr.flags ^= RXRPC_CLIENT_INITIATED; 611 whdr.flags &= RXRPC_CLIENT_INITIATED; 612 613 ret = kernel_sendmsg(local->socket, &msg, 614 iov, ioc, size); 615 if (ret < 0) 616 trace_rxrpc_tx_fail(local->debug_id, 0, ret, 617 rxrpc_tx_point_reject); 618 else 619 trace_rxrpc_tx_packet(local->debug_id, &whdr, 620 rxrpc_tx_point_reject); 621 } 622 623 rxrpc_free_skb(skb, rxrpc_skb_freed); 624 } 625 626 _leave(""); 627} 628 629/* 630 * Send a VERSION reply to a peer as a keepalive. 631 */ 632void rxrpc_send_keepalive(struct rxrpc_peer *peer) 633{ 634 struct rxrpc_wire_header whdr; 635 struct msghdr msg; 636 struct kvec iov[2]; 637 size_t len; 638 int ret; 639 640 _enter(""); 641 642 msg.msg_name = &peer->srx.transport; 643 msg.msg_namelen = peer->srx.transport_len; 644 msg.msg_control = NULL; 645 msg.msg_controllen = 0; 646 msg.msg_flags = 0; 647 648 whdr.epoch = htonl(peer->local->rxnet->epoch); 649 whdr.cid = 0; 650 whdr.callNumber = 0; 651 whdr.seq = 0; 652 whdr.serial = 0; 653 whdr.type = RXRPC_PACKET_TYPE_VERSION; /* Not client-initiated */ 654 whdr.flags = RXRPC_LAST_PACKET; 655 whdr.userStatus = 0; 656 whdr.securityIndex = 0; 657 whdr._rsvd = 0; 658 whdr.serviceId = 0; 659 660 iov[0].iov_base = &whdr; 661 iov[0].iov_len = sizeof(whdr); 662 iov[1].iov_base = (char *)rxrpc_keepalive_string; 663 iov[1].iov_len = sizeof(rxrpc_keepalive_string); 664 665 len = iov[0].iov_len + iov[1].iov_len; 666 667 _proto("Tx VERSION (keepalive)"); 668 669 ret = kernel_sendmsg(peer->local->socket, &msg, iov, 2, len); 670 if (ret < 0) 671 trace_rxrpc_tx_fail(peer->debug_id, 0, ret, 672 rxrpc_tx_point_version_keepalive); 673 else 674 trace_rxrpc_tx_packet(peer->debug_id, &whdr, 675 rxrpc_tx_point_version_keepalive); 676 677 peer->last_tx_at = ktime_get_seconds(); 678 _leave(""); 679} 680