1 /* connection-level event handling 2 * 3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. 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 12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 13 14 #include <linux/module.h> 15 #include <linux/net.h> 16 #include <linux/skbuff.h> 17 #include <linux/errqueue.h> 18 #include <linux/udp.h> 19 #include <linux/in.h> 20 #include <linux/in6.h> 21 #include <linux/icmp.h> 22 #include <net/sock.h> 23 #include <net/af_rxrpc.h> 24 #include <net/ip.h> 25 #include "ar-internal.h" 26 27 /* 28 * pass a connection-level abort onto all calls on that connection 29 */ 30 static void rxrpc_abort_calls(struct rxrpc_connection *conn, int state, 31 u32 abort_code) 32 { 33 struct rxrpc_call *call; 34 struct rb_node *p; 35 36 _enter("{%d},%x", conn->debug_id, abort_code); 37 38 read_lock_bh(&conn->lock); 39 40 for (p = rb_first(&conn->calls); p; p = rb_next(p)) { 41 call = rb_entry(p, struct rxrpc_call, conn_node); 42 write_lock(&call->state_lock); 43 if (call->state <= RXRPC_CALL_COMPLETE) { 44 call->state = state; 45 if (state == RXRPC_CALL_LOCALLY_ABORTED) { 46 call->local_abort = conn->local_abort; 47 set_bit(RXRPC_CALL_EV_CONN_ABORT, &call->events); 48 } else { 49 call->remote_abort = conn->remote_abort; 50 set_bit(RXRPC_CALL_EV_RCVD_ABORT, &call->events); 51 } 52 rxrpc_queue_call(call); 53 } 54 write_unlock(&call->state_lock); 55 } 56 57 read_unlock_bh(&conn->lock); 58 _leave(""); 59 } 60 61 /* 62 * generate a connection-level abort 63 */ 64 static int rxrpc_abort_connection(struct rxrpc_connection *conn, 65 u32 error, u32 abort_code) 66 { 67 struct rxrpc_wire_header whdr; 68 struct msghdr msg; 69 struct kvec iov[2]; 70 __be32 word; 71 size_t len; 72 u32 serial; 73 int ret; 74 75 _enter("%d,,%u,%u", conn->debug_id, error, abort_code); 76 77 /* generate a connection-level abort */ 78 spin_lock_bh(&conn->state_lock); 79 if (conn->state < RXRPC_CONN_REMOTELY_ABORTED) { 80 conn->state = RXRPC_CONN_LOCALLY_ABORTED; 81 conn->error = error; 82 spin_unlock_bh(&conn->state_lock); 83 } else { 84 spin_unlock_bh(&conn->state_lock); 85 _leave(" = 0 [already dead]"); 86 return 0; 87 } 88 89 rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, abort_code); 90 91 msg.msg_name = &conn->trans->peer->srx.transport; 92 msg.msg_namelen = conn->trans->peer->srx.transport_len; 93 msg.msg_control = NULL; 94 msg.msg_controllen = 0; 95 msg.msg_flags = 0; 96 97 whdr.epoch = htonl(conn->epoch); 98 whdr.cid = htonl(conn->cid); 99 whdr.callNumber = 0; 100 whdr.seq = 0; 101 whdr.type = RXRPC_PACKET_TYPE_ABORT; 102 whdr.flags = conn->out_clientflag; 103 whdr.userStatus = 0; 104 whdr.securityIndex = conn->security_ix; 105 whdr._rsvd = 0; 106 whdr.serviceId = htons(conn->service_id); 107 108 word = htonl(conn->local_abort); 109 110 iov[0].iov_base = &whdr; 111 iov[0].iov_len = sizeof(whdr); 112 iov[1].iov_base = &word; 113 iov[1].iov_len = sizeof(word); 114 115 len = iov[0].iov_len + iov[1].iov_len; 116 117 serial = atomic_inc_return(&conn->serial); 118 whdr.serial = htonl(serial); 119 _proto("Tx CONN ABORT %%%u { %d }", serial, conn->local_abort); 120 121 ret = kernel_sendmsg(conn->trans->local->socket, &msg, iov, 2, len); 122 if (ret < 0) { 123 _debug("sendmsg failed: %d", ret); 124 return -EAGAIN; 125 } 126 127 _leave(" = 0"); 128 return 0; 129 } 130 131 /* 132 * mark a call as being on a now-secured channel 133 * - must be called with softirqs disabled 134 */ 135 static void rxrpc_call_is_secure(struct rxrpc_call *call) 136 { 137 _enter("%p", call); 138 if (call) { 139 read_lock(&call->state_lock); 140 if (call->state < RXRPC_CALL_COMPLETE && 141 !test_and_set_bit(RXRPC_CALL_EV_SECURED, &call->events)) 142 rxrpc_queue_call(call); 143 read_unlock(&call->state_lock); 144 } 145 } 146 147 /* 148 * connection-level Rx packet processor 149 */ 150 static int rxrpc_process_event(struct rxrpc_connection *conn, 151 struct sk_buff *skb, 152 u32 *_abort_code) 153 { 154 struct rxrpc_skb_priv *sp = rxrpc_skb(skb); 155 __be32 wtmp; 156 u32 abort_code; 157 int loop, ret; 158 159 if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) { 160 kleave(" = -ECONNABORTED [%u]", conn->state); 161 return -ECONNABORTED; 162 } 163 164 _enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial); 165 166 switch (sp->hdr.type) { 167 case RXRPC_PACKET_TYPE_ABORT: 168 if (skb_copy_bits(skb, 0, &wtmp, sizeof(wtmp)) < 0) 169 return -EPROTO; 170 abort_code = ntohl(wtmp); 171 _proto("Rx ABORT %%%u { ac=%d }", sp->hdr.serial, abort_code); 172 173 conn->state = RXRPC_CONN_REMOTELY_ABORTED; 174 rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED, 175 abort_code); 176 return -ECONNABORTED; 177 178 case RXRPC_PACKET_TYPE_CHALLENGE: 179 return conn->security->respond_to_challenge(conn, skb, 180 _abort_code); 181 182 case RXRPC_PACKET_TYPE_RESPONSE: 183 ret = conn->security->verify_response(conn, skb, _abort_code); 184 if (ret < 0) 185 return ret; 186 187 ret = conn->security->init_connection_security(conn); 188 if (ret < 0) 189 return ret; 190 191 conn->security->prime_packet_security(conn); 192 read_lock_bh(&conn->lock); 193 spin_lock(&conn->state_lock); 194 195 if (conn->state == RXRPC_CONN_SERVER_CHALLENGING) { 196 conn->state = RXRPC_CONN_SERVER; 197 for (loop = 0; loop < RXRPC_MAXCALLS; loop++) 198 rxrpc_call_is_secure(conn->channels[loop]); 199 } 200 201 spin_unlock(&conn->state_lock); 202 read_unlock_bh(&conn->lock); 203 return 0; 204 205 default: 206 _leave(" = -EPROTO [%u]", sp->hdr.type); 207 return -EPROTO; 208 } 209 } 210 211 /* 212 * set up security and issue a challenge 213 */ 214 static void rxrpc_secure_connection(struct rxrpc_connection *conn) 215 { 216 u32 abort_code; 217 int ret; 218 219 _enter("{%d}", conn->debug_id); 220 221 ASSERT(conn->security_ix != 0); 222 223 if (!conn->key) { 224 _debug("set up security"); 225 ret = rxrpc_init_server_conn_security(conn); 226 switch (ret) { 227 case 0: 228 break; 229 case -ENOENT: 230 abort_code = RX_CALL_DEAD; 231 goto abort; 232 default: 233 abort_code = RXKADNOAUTH; 234 goto abort; 235 } 236 } 237 238 if (conn->security->issue_challenge(conn) < 0) { 239 abort_code = RX_CALL_DEAD; 240 ret = -ENOMEM; 241 goto abort; 242 } 243 244 _leave(""); 245 return; 246 247 abort: 248 _debug("abort %d, %d", ret, abort_code); 249 rxrpc_abort_connection(conn, -ret, abort_code); 250 _leave(" [aborted]"); 251 } 252 253 /* 254 * connection-level event processor 255 */ 256 void rxrpc_process_connection(struct work_struct *work) 257 { 258 struct rxrpc_connection *conn = 259 container_of(work, struct rxrpc_connection, processor); 260 struct sk_buff *skb; 261 u32 abort_code = RX_PROTOCOL_ERROR; 262 int ret; 263 264 _enter("{%d}", conn->debug_id); 265 266 atomic_inc(&conn->usage); 267 268 if (test_and_clear_bit(RXRPC_CONN_CHALLENGE, &conn->events)) { 269 rxrpc_secure_connection(conn); 270 rxrpc_put_connection(conn); 271 } 272 273 /* go through the conn-level event packets, releasing the ref on this 274 * connection that each one has when we've finished with it */ 275 while ((skb = skb_dequeue(&conn->rx_queue))) { 276 ret = rxrpc_process_event(conn, skb, &abort_code); 277 switch (ret) { 278 case -EPROTO: 279 case -EKEYEXPIRED: 280 case -EKEYREJECTED: 281 goto protocol_error; 282 case -EAGAIN: 283 goto requeue_and_leave; 284 case -ECONNABORTED: 285 default: 286 rxrpc_put_connection(conn); 287 rxrpc_free_skb(skb); 288 break; 289 } 290 } 291 292 out: 293 rxrpc_put_connection(conn); 294 _leave(""); 295 return; 296 297 requeue_and_leave: 298 skb_queue_head(&conn->rx_queue, skb); 299 goto out; 300 301 protocol_error: 302 if (rxrpc_abort_connection(conn, -ret, abort_code) < 0) 303 goto requeue_and_leave; 304 rxrpc_put_connection(conn); 305 rxrpc_free_skb(skb); 306 _leave(" [EPROTO]"); 307 goto out; 308 } 309 310 /* 311 * put a packet up for transport-level abort 312 */ 313 void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb) 314 { 315 CHECK_SLAB_OKAY(&local->usage); 316 317 if (!atomic_inc_not_zero(&local->usage)) { 318 printk("resurrected on reject\n"); 319 BUG(); 320 } 321 322 skb_queue_tail(&local->reject_queue, skb); 323 rxrpc_queue_work(&local->rejecter); 324 } 325 326 /* 327 * reject packets through the local endpoint 328 */ 329 void rxrpc_reject_packets(struct work_struct *work) 330 { 331 union { 332 struct sockaddr sa; 333 struct sockaddr_in sin; 334 } sa; 335 struct rxrpc_skb_priv *sp; 336 struct rxrpc_wire_header whdr; 337 struct rxrpc_local *local; 338 struct sk_buff *skb; 339 struct msghdr msg; 340 struct kvec iov[2]; 341 size_t size; 342 __be32 code; 343 344 local = container_of(work, struct rxrpc_local, rejecter); 345 rxrpc_get_local(local); 346 347 _enter("%d", local->debug_id); 348 349 iov[0].iov_base = &whdr; 350 iov[0].iov_len = sizeof(whdr); 351 iov[1].iov_base = &code; 352 iov[1].iov_len = sizeof(code); 353 size = sizeof(whdr) + sizeof(code); 354 355 msg.msg_name = &sa; 356 msg.msg_control = NULL; 357 msg.msg_controllen = 0; 358 msg.msg_flags = 0; 359 360 memset(&sa, 0, sizeof(sa)); 361 sa.sa.sa_family = local->srx.transport.family; 362 switch (sa.sa.sa_family) { 363 case AF_INET: 364 msg.msg_namelen = sizeof(sa.sin); 365 break; 366 default: 367 msg.msg_namelen = 0; 368 break; 369 } 370 371 memset(&whdr, 0, sizeof(whdr)); 372 whdr.type = RXRPC_PACKET_TYPE_ABORT; 373 374 while ((skb = skb_dequeue(&local->reject_queue))) { 375 sp = rxrpc_skb(skb); 376 switch (sa.sa.sa_family) { 377 case AF_INET: 378 sa.sin.sin_port = udp_hdr(skb)->source; 379 sa.sin.sin_addr.s_addr = ip_hdr(skb)->saddr; 380 code = htonl(skb->priority); 381 382 whdr.epoch = htonl(sp->hdr.epoch); 383 whdr.cid = htonl(sp->hdr.cid); 384 whdr.callNumber = htonl(sp->hdr.callNumber); 385 whdr.serviceId = htons(sp->hdr.serviceId); 386 whdr.flags = sp->hdr.flags; 387 whdr.flags ^= RXRPC_CLIENT_INITIATED; 388 whdr.flags &= RXRPC_CLIENT_INITIATED; 389 390 kernel_sendmsg(local->socket, &msg, iov, 2, size); 391 break; 392 393 default: 394 break; 395 } 396 397 rxrpc_free_skb(skb); 398 rxrpc_put_local(local); 399 } 400 401 rxrpc_put_local(local); 402 _leave(""); 403 } 404