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