1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* connection-level event handling 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/module.h> 11 #include <linux/net.h> 12 #include <linux/skbuff.h> 13 #include <linux/errqueue.h> 14 #include <net/sock.h> 15 #include <net/af_rxrpc.h> 16 #include <net/ip.h> 17 #include "ar-internal.h" 18 19 /* 20 * Set the completion state on an aborted connection. 21 */ 22 static bool rxrpc_set_conn_aborted(struct rxrpc_connection *conn, struct sk_buff *skb, 23 s32 abort_code, int err, 24 enum rxrpc_call_completion compl) 25 { 26 bool aborted = false; 27 28 if (conn->state != RXRPC_CONN_ABORTED) { 29 spin_lock(&conn->state_lock); 30 if (conn->state != RXRPC_CONN_ABORTED) { 31 conn->abort_code = abort_code; 32 conn->error = err; 33 conn->completion = compl; 34 /* Order the abort info before the state change. */ 35 smp_store_release(&conn->state, RXRPC_CONN_ABORTED); 36 set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags); 37 set_bit(RXRPC_CONN_EV_ABORT_CALLS, &conn->events); 38 aborted = true; 39 } 40 spin_unlock(&conn->state_lock); 41 } 42 43 return aborted; 44 } 45 46 /* 47 * Mark a socket buffer to indicate that the connection it's on should be aborted. 48 */ 49 int rxrpc_abort_conn(struct rxrpc_connection *conn, struct sk_buff *skb, 50 s32 abort_code, int err, enum rxrpc_abort_reason why) 51 { 52 struct rxrpc_skb_priv *sp = rxrpc_skb(skb); 53 54 if (rxrpc_set_conn_aborted(conn, skb, abort_code, err, 55 RXRPC_CALL_LOCALLY_ABORTED)) { 56 trace_rxrpc_abort(0, why, sp->hdr.cid, sp->hdr.callNumber, 57 sp->hdr.seq, abort_code, err); 58 rxrpc_poke_conn(conn, rxrpc_conn_get_poke_abort); 59 } 60 return -EPROTO; 61 } 62 63 /* 64 * Mark a connection as being remotely aborted. 65 */ 66 static void rxrpc_input_conn_abort(struct rxrpc_connection *conn, 67 struct sk_buff *skb) 68 { 69 trace_rxrpc_rx_conn_abort(conn, skb); 70 rxrpc_set_conn_aborted(conn, skb, skb->priority, -ECONNABORTED, 71 RXRPC_CALL_REMOTELY_ABORTED); 72 } 73 74 /* 75 * Retransmit terminal ACK or ABORT of the previous call. 76 */ 77 void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn, 78 struct sk_buff *skb, 79 unsigned int channel) 80 { 81 struct rxrpc_skb_priv *sp = skb ? rxrpc_skb(skb) : NULL; 82 struct rxrpc_channel *chan; 83 struct msghdr msg; 84 struct kvec iov[3]; 85 struct { 86 struct rxrpc_wire_header whdr; 87 union { 88 __be32 abort_code; 89 struct rxrpc_ackpacket ack; 90 }; 91 } __attribute__((packed)) pkt; 92 struct rxrpc_acktrailer trailer; 93 size_t len; 94 int ret, ioc; 95 u32 serial, mtu, call_id, padding; 96 97 _enter("%d", conn->debug_id); 98 99 if (sp && sp->hdr.type == RXRPC_PACKET_TYPE_ACK) { 100 if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header), 101 &pkt.ack, sizeof(pkt.ack)) < 0) 102 return; 103 if (pkt.ack.reason == RXRPC_ACK_PING_RESPONSE) 104 return; 105 } 106 107 chan = &conn->channels[channel]; 108 109 /* If the last call got moved on whilst we were waiting to run, just 110 * ignore this packet. 111 */ 112 call_id = chan->last_call; 113 if (skb && call_id != sp->hdr.callNumber) 114 return; 115 116 msg.msg_name = &conn->peer->srx.transport; 117 msg.msg_namelen = conn->peer->srx.transport_len; 118 msg.msg_control = NULL; 119 msg.msg_controllen = 0; 120 msg.msg_flags = 0; 121 122 iov[0].iov_base = &pkt; 123 iov[0].iov_len = sizeof(pkt.whdr); 124 iov[1].iov_base = &padding; 125 iov[1].iov_len = 3; 126 iov[2].iov_base = &trailer; 127 iov[2].iov_len = sizeof(trailer); 128 129 serial = rxrpc_get_next_serial(conn); 130 131 pkt.whdr.epoch = htonl(conn->proto.epoch); 132 pkt.whdr.cid = htonl(conn->proto.cid | channel); 133 pkt.whdr.callNumber = htonl(call_id); 134 pkt.whdr.serial = htonl(serial); 135 pkt.whdr.seq = 0; 136 pkt.whdr.type = chan->last_type; 137 pkt.whdr.flags = conn->out_clientflag; 138 pkt.whdr.userStatus = 0; 139 pkt.whdr.securityIndex = conn->security_ix; 140 pkt.whdr._rsvd = 0; 141 pkt.whdr.serviceId = htons(conn->service_id); 142 143 len = sizeof(pkt.whdr); 144 switch (chan->last_type) { 145 case RXRPC_PACKET_TYPE_ABORT: 146 pkt.abort_code = htonl(chan->last_abort); 147 iov[0].iov_len += sizeof(pkt.abort_code); 148 len += sizeof(pkt.abort_code); 149 ioc = 1; 150 break; 151 152 case RXRPC_PACKET_TYPE_ACK: 153 mtu = conn->peer->if_mtu; 154 mtu -= conn->peer->hdrsize; 155 pkt.ack.bufferSpace = 0; 156 pkt.ack.maxSkew = htons(skb ? skb->priority : 0); 157 pkt.ack.firstPacket = htonl(chan->last_seq + 1); 158 pkt.ack.previousPacket = htonl(chan->last_seq); 159 pkt.ack.serial = htonl(skb ? sp->hdr.serial : 0); 160 pkt.ack.reason = skb ? RXRPC_ACK_DUPLICATE : RXRPC_ACK_IDLE; 161 pkt.ack.nAcks = 0; 162 trailer.maxMTU = htonl(rxrpc_rx_mtu); 163 trailer.ifMTU = htonl(mtu); 164 trailer.rwind = htonl(rxrpc_rx_window_size); 165 trailer.jumbo_max = htonl(rxrpc_rx_jumbo_max); 166 pkt.whdr.flags |= RXRPC_SLOW_START_OK; 167 padding = 0; 168 iov[0].iov_len += sizeof(pkt.ack); 169 len += sizeof(pkt.ack) + 3 + sizeof(trailer); 170 ioc = 3; 171 172 trace_rxrpc_tx_ack(chan->call_debug_id, serial, 173 ntohl(pkt.ack.firstPacket), 174 ntohl(pkt.ack.serial), 175 pkt.ack.reason, 0, rxrpc_rx_window_size); 176 break; 177 178 default: 179 return; 180 } 181 182 ret = kernel_sendmsg(conn->local->socket, &msg, iov, ioc, len); 183 conn->peer->last_tx_at = ktime_get_seconds(); 184 if (ret < 0) 185 trace_rxrpc_tx_fail(chan->call_debug_id, serial, ret, 186 rxrpc_tx_point_call_final_resend); 187 else 188 trace_rxrpc_tx_packet(chan->call_debug_id, &pkt.whdr, 189 rxrpc_tx_point_call_final_resend); 190 191 _leave(""); 192 } 193 194 /* 195 * pass a connection-level abort onto all calls on that connection 196 */ 197 static void rxrpc_abort_calls(struct rxrpc_connection *conn) 198 { 199 struct rxrpc_call *call; 200 int i; 201 202 _enter("{%d},%x", conn->debug_id, conn->abort_code); 203 204 for (i = 0; i < RXRPC_MAXCALLS; i++) { 205 call = conn->channels[i].call; 206 if (call) { 207 rxrpc_see_call(call, rxrpc_call_see_conn_abort); 208 rxrpc_set_call_completion(call, 209 conn->completion, 210 conn->abort_code, 211 conn->error); 212 rxrpc_poke_call(call, rxrpc_call_poke_conn_abort); 213 } 214 } 215 216 _leave(""); 217 } 218 219 /* 220 * mark a call as being on a now-secured channel 221 * - must be called with BH's disabled. 222 */ 223 static void rxrpc_call_is_secure(struct rxrpc_call *call) 224 { 225 if (call && __rxrpc_call_state(call) == RXRPC_CALL_SERVER_SECURING) { 226 rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST); 227 rxrpc_notify_socket(call); 228 } 229 } 230 231 /* 232 * connection-level Rx packet processor 233 */ 234 static int rxrpc_process_event(struct rxrpc_connection *conn, 235 struct sk_buff *skb) 236 { 237 struct rxrpc_skb_priv *sp = rxrpc_skb(skb); 238 int ret; 239 240 if (conn->state == RXRPC_CONN_ABORTED) 241 return -ECONNABORTED; 242 243 _enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial); 244 245 switch (sp->hdr.type) { 246 case RXRPC_PACKET_TYPE_CHALLENGE: 247 return conn->security->respond_to_challenge(conn, skb); 248 249 case RXRPC_PACKET_TYPE_RESPONSE: 250 ret = conn->security->verify_response(conn, skb); 251 if (ret < 0) 252 return ret; 253 254 ret = conn->security->init_connection_security( 255 conn, conn->key->payload.data[0]); 256 if (ret < 0) 257 return ret; 258 259 spin_lock(&conn->state_lock); 260 if (conn->state == RXRPC_CONN_SERVICE_CHALLENGING) 261 conn->state = RXRPC_CONN_SERVICE; 262 spin_unlock(&conn->state_lock); 263 264 if (conn->state == RXRPC_CONN_SERVICE) { 265 /* Offload call state flipping to the I/O thread. As 266 * we've already received the packet, put it on the 267 * front of the queue. 268 */ 269 skb->mark = RXRPC_SKB_MARK_SERVICE_CONN_SECURED; 270 rxrpc_get_skb(skb, rxrpc_skb_get_conn_secured); 271 skb_queue_head(&conn->local->rx_queue, skb); 272 rxrpc_wake_up_io_thread(conn->local); 273 } 274 return 0; 275 276 default: 277 WARN_ON_ONCE(1); 278 return -EPROTO; 279 } 280 } 281 282 /* 283 * set up security and issue a challenge 284 */ 285 static void rxrpc_secure_connection(struct rxrpc_connection *conn) 286 { 287 if (conn->security->issue_challenge(conn) < 0) 288 rxrpc_abort_conn(conn, NULL, RX_CALL_DEAD, -ENOMEM, 289 rxrpc_abort_nomem); 290 } 291 292 /* 293 * Process delayed final ACKs that we haven't subsumed into a subsequent call. 294 */ 295 void rxrpc_process_delayed_final_acks(struct rxrpc_connection *conn, bool force) 296 { 297 unsigned long j = jiffies, next_j; 298 unsigned int channel; 299 bool set; 300 301 again: 302 next_j = j + LONG_MAX; 303 set = false; 304 for (channel = 0; channel < RXRPC_MAXCALLS; channel++) { 305 struct rxrpc_channel *chan = &conn->channels[channel]; 306 unsigned long ack_at; 307 308 if (!test_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags)) 309 continue; 310 311 ack_at = chan->final_ack_at; 312 if (time_before(j, ack_at) && !force) { 313 if (time_before(ack_at, next_j)) { 314 next_j = ack_at; 315 set = true; 316 } 317 continue; 318 } 319 320 if (test_and_clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel, 321 &conn->flags)) 322 rxrpc_conn_retransmit_call(conn, NULL, channel); 323 } 324 325 j = jiffies; 326 if (time_before_eq(next_j, j)) 327 goto again; 328 if (set) 329 rxrpc_reduce_conn_timer(conn, next_j); 330 } 331 332 /* 333 * connection-level event processor 334 */ 335 static void rxrpc_do_process_connection(struct rxrpc_connection *conn) 336 { 337 struct sk_buff *skb; 338 int ret; 339 340 if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events)) 341 rxrpc_secure_connection(conn); 342 343 /* go through the conn-level event packets, releasing the ref on this 344 * connection that each one has when we've finished with it */ 345 while ((skb = skb_dequeue(&conn->rx_queue))) { 346 rxrpc_see_skb(skb, rxrpc_skb_see_conn_work); 347 ret = rxrpc_process_event(conn, skb); 348 switch (ret) { 349 case -ENOMEM: 350 case -EAGAIN: 351 skb_queue_head(&conn->rx_queue, skb); 352 rxrpc_queue_conn(conn, rxrpc_conn_queue_retry_work); 353 break; 354 default: 355 rxrpc_free_skb(skb, rxrpc_skb_put_conn_work); 356 break; 357 } 358 } 359 } 360 361 void rxrpc_process_connection(struct work_struct *work) 362 { 363 struct rxrpc_connection *conn = 364 container_of(work, struct rxrpc_connection, processor); 365 366 rxrpc_see_connection(conn, rxrpc_conn_see_work); 367 368 if (__rxrpc_use_local(conn->local, rxrpc_local_use_conn_work)) { 369 rxrpc_do_process_connection(conn); 370 rxrpc_unuse_local(conn->local, rxrpc_local_unuse_conn_work); 371 } 372 } 373 374 /* 375 * post connection-level events to the connection 376 * - this includes challenges, responses, some aborts and call terminal packet 377 * retransmission. 378 */ 379 static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn, 380 struct sk_buff *skb) 381 { 382 _enter("%p,%p", conn, skb); 383 384 rxrpc_get_skb(skb, rxrpc_skb_get_conn_work); 385 skb_queue_tail(&conn->rx_queue, skb); 386 rxrpc_queue_conn(conn, rxrpc_conn_queue_rx_work); 387 } 388 389 /* 390 * Input a connection-level packet. 391 */ 392 bool rxrpc_input_conn_packet(struct rxrpc_connection *conn, struct sk_buff *skb) 393 { 394 struct rxrpc_skb_priv *sp = rxrpc_skb(skb); 395 396 switch (sp->hdr.type) { 397 case RXRPC_PACKET_TYPE_BUSY: 398 /* Just ignore BUSY packets for now. */ 399 return true; 400 401 case RXRPC_PACKET_TYPE_ABORT: 402 if (rxrpc_is_conn_aborted(conn)) 403 return true; 404 rxrpc_input_conn_abort(conn, skb); 405 rxrpc_abort_calls(conn); 406 return true; 407 408 case RXRPC_PACKET_TYPE_CHALLENGE: 409 case RXRPC_PACKET_TYPE_RESPONSE: 410 if (rxrpc_is_conn_aborted(conn)) { 411 if (conn->completion == RXRPC_CALL_LOCALLY_ABORTED) 412 rxrpc_send_conn_abort(conn); 413 return true; 414 } 415 rxrpc_post_packet_to_conn(conn, skb); 416 return true; 417 418 default: 419 WARN_ON_ONCE(1); 420 return true; 421 } 422 } 423 424 /* 425 * Input a connection event. 426 */ 427 void rxrpc_input_conn_event(struct rxrpc_connection *conn, struct sk_buff *skb) 428 { 429 unsigned int loop; 430 431 if (test_and_clear_bit(RXRPC_CONN_EV_ABORT_CALLS, &conn->events)) 432 rxrpc_abort_calls(conn); 433 434 switch (skb->mark) { 435 case RXRPC_SKB_MARK_SERVICE_CONN_SECURED: 436 if (conn->state != RXRPC_CONN_SERVICE) 437 break; 438 439 for (loop = 0; loop < RXRPC_MAXCALLS; loop++) 440 rxrpc_call_is_secure(conn->channels[loop].call); 441 break; 442 } 443 444 /* Process delayed ACKs whose time has come. */ 445 if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK) 446 rxrpc_process_delayed_final_acks(conn, false); 447 } 448