net/rxrpc/ar-connevent.c

   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 #include <linux/module.h>
  13 #include <linux/net.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/errqueue.h>
  16 #include <linux/udp.h>
  17 #include <linux/in.h>
  18 #include <linux/in6.h>
  19 #include <linux/icmp.h>
  20 #include <net/sock.h>
  21 #include <net/af_rxrpc.h>
  22 #include <net/ip.h>
  23 #include "ar-internal.h"
  24
  25 /*
  26  * pass a connection-level abort onto all calls on that connection
  27  */
  28 static void rxrpc_abort_calls(struct rxrpc_connection *conn, int state,
  29                               u32 abort_code)
  30 {
  31         struct rxrpc_call *call;
  32         struct rb_node *p;
  33
  34         _enter("{%d},%x", conn->debug_id, abort_code);
  35
  36         read_lock_bh(&conn->lock);
  37
  38         for (p = rb_first(&conn->calls); p; p = rb_next(p)) {
  39                 call = rb_entry(p, struct rxrpc_call, conn_node);
  40                 write_lock(&call->state_lock);
  41                 if (call->state <= RXRPC_CALL_COMPLETE) {
  42                         call->state = state;
  43                         if (state == RXRPC_CALL_LOCALLY_ABORTED) {
  44                                 call->local_abort = conn->local_abort;
  45                                 set_bit(RXRPC_CALL_EV_CONN_ABORT, &call->events);
  46                         } else {
  47                                 call->remote_abort = conn->remote_abort;
  48                                 set_bit(RXRPC_CALL_EV_RCVD_ABORT, &call->events);
  49                         }
  50                         rxrpc_queue_call(call);
  51                 }
  52                 write_unlock(&call->state_lock);
  53         }
  54
  55         read_unlock_bh(&conn->lock);
  56         _leave("");
  57 }
  58
  59 /*
  60  * generate a connection-level abort
  61  */
  62 static int rxrpc_abort_connection(struct rxrpc_connection *conn,
  63                                   u32 error, u32 abort_code)
  64 {
  65         struct rxrpc_wire_header whdr;
  66         struct msghdr msg;
  67         struct kvec iov[2];
  68         __be32 word;
  69         size_t len;
  70         u32 serial;
  71         int ret;
  72
  73         _enter("%d,,%u,%u", conn->debug_id, error, abort_code);
  74
  75         /* generate a connection-level abort */
  76         spin_lock_bh(&conn->state_lock);
  77         if (conn->state < RXRPC_CONN_REMOTELY_ABORTED) {
  78                 conn->state = RXRPC_CONN_LOCALLY_ABORTED;
  79                 conn->error = error;
  80                 spin_unlock_bh(&conn->state_lock);
  81         } else {
  82                 spin_unlock_bh(&conn->state_lock);
  83                 _leave(" = 0 [already dead]");
  84                 return 0;
  85         }
  86
  87         rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, abort_code);
  88
  89         msg.msg_name    = &conn->trans->peer->srx.transport;
  90         msg.msg_namelen = conn->trans->peer->srx.transport_len;
  91         msg.msg_control = NULL;
  92         msg.msg_controllen = 0;
  93         msg.msg_flags   = 0;
  94
  95         whdr.epoch      = htonl(conn->epoch);
  96         whdr.cid        = htonl(conn->cid);
  97         whdr.callNumber = 0;
  98         whdr.seq        = 0;
  99         whdr.type       = RXRPC_PACKET_TYPE_ABORT;
 100         whdr.flags      = conn->out_clientflag;
 101         whdr.userStatus = 0;
 102         whdr.securityIndex = conn->security_ix;
 103         whdr._rsvd      = 0;
 104         whdr.serviceId  = htons(conn->service_id);
 105
 106         word            = htonl(conn->local_abort);
 107
 108         iov[0].iov_base = &whdr;
 109         iov[0].iov_len  = sizeof(whdr);
 110         iov[1].iov_base = &word;
 111         iov[1].iov_len  = sizeof(word);
 112
 113         len = iov[0].iov_len + iov[1].iov_len;
 114
 115         serial = atomic_inc_return(&conn->serial);
 116         whdr.serial = htonl(serial);
 117         _proto("Tx CONN ABORT %%%u { %d }", serial, conn->local_abort);
 118
 119         ret = kernel_sendmsg(conn->trans->local->socket, &msg, iov, 2, len);
 120         if (ret < 0) {
 121                 _debug("sendmsg failed: %d", ret);
 122                 return -EAGAIN;
 123         }
 124
 125         _leave(" = 0");
 126         return 0;
 127 }
 128
 129 /*
 130  * mark a call as being on a now-secured channel
 131  * - must be called with softirqs disabled
 132  */
 133 static void rxrpc_call_is_secure(struct rxrpc_call *call)
 134 {
 135         _enter("%p", call);
 136         if (call) {
 137                 read_lock(&call->state_lock);
 138                 if (call->state < RXRPC_CALL_COMPLETE &&
 139                     !test_and_set_bit(RXRPC_CALL_EV_SECURED, &call->events))
 140                         rxrpc_queue_call(call);
 141                 read_unlock(&call->state_lock);
 142         }
 143 }
 144
 145 /*
 146  * connection-level Rx packet processor
 147  */
 148 static int rxrpc_process_event(struct rxrpc_connection *conn,
 149                                struct sk_buff *skb,
 150                                u32 *_abort_code)
 151 {
 152         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 153         __be32 wtmp;
 154         u32 abort_code;
 155         int loop, ret;
 156
 157         if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
 158                 kleave(" = -ECONNABORTED [%u]", conn->state);
 159                 return -ECONNABORTED;
 160         }
 161
 162         _enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial);
 163
 164         switch (sp->hdr.type) {
 165         case RXRPC_PACKET_TYPE_ABORT:
 166                 if (skb_copy_bits(skb, 0, &wtmp, sizeof(wtmp)) < 0)
 167                         return -EPROTO;
 168                 abort_code = ntohl(wtmp);
 169                 _proto("Rx ABORT %%%u { ac=%d }", sp->hdr.serial, abort_code);
 170
 171                 conn->state = RXRPC_CONN_REMOTELY_ABORTED;
 172                 rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED,
 173                                   abort_code);
 174                 return -ECONNABORTED;
 175
 176         case RXRPC_PACKET_TYPE_CHALLENGE:
 177                 if (conn->security)
 178                         return conn->security->respond_to_challenge(
 179                                 conn, skb, _abort_code);
 180                 return -EPROTO;
 181
 182         case RXRPC_PACKET_TYPE_RESPONSE:
 183                 if (!conn->security)
 184                         return -EPROTO;
 185
 186                 ret = conn->security->verify_response(conn, skb, _abort_code);
 187                 if (ret < 0)
 188                         return ret;
 189
 190                 ret = conn->security->init_connection_security(conn);
 191                 if (ret < 0)
 192                         return ret;
 193
 194                 conn->security->prime_packet_security(conn);
 195                 read_lock_bh(&conn->lock);
 196                 spin_lock(&conn->state_lock);
 197
 198                 if (conn->state == RXRPC_CONN_SERVER_CHALLENGING) {
 199                         conn->state = RXRPC_CONN_SERVER;
 200                         for (loop = 0; loop < RXRPC_MAXCALLS; loop++)
 201                                 rxrpc_call_is_secure(conn->channels[loop]);
 202                 }
 203
 204                 spin_unlock(&conn->state_lock);
 205                 read_unlock_bh(&conn->lock);
 206                 return 0;
 207
 208         default:
 209                 _leave(" = -EPROTO [%u]", sp->hdr.type);
 210                 return -EPROTO;
 211         }
 212 }
 213
 214 /*
 215  * set up security and issue a challenge
 216  */
 217 static void rxrpc_secure_connection(struct rxrpc_connection *conn)
 218 {
 219         u32 abort_code;
 220         int ret;
 221
 222         _enter("{%d}", conn->debug_id);
 223
 224         ASSERT(conn->security_ix != 0);
 225
 226         if (!conn->key) {
 227                 _debug("set up security");
 228                 ret = rxrpc_init_server_conn_security(conn);
 229                 switch (ret) {
 230                 case 0:
 231                         break;
 232                 case -ENOENT:
 233                         abort_code = RX_CALL_DEAD;
 234                         goto abort;
 235                 default:
 236                         abort_code = RXKADNOAUTH;
 237                         goto abort;
 238                 }
 239         }
 240
 241         ASSERT(conn->security != NULL);
 242
 243         if (conn->security->issue_challenge(conn) < 0) {
 244                 abort_code = RX_CALL_DEAD;
 245                 ret = -ENOMEM;
 246                 goto abort;
 247         }
 248
 249         _leave("");
 250         return;
 251
 252 abort:
 253         _debug("abort %d, %d", ret, abort_code);
 254         rxrpc_abort_connection(conn, -ret, abort_code);
 255         _leave(" [aborted]");
 256 }
 257
 258 /*
 259  * connection-level event processor
 260  */
 261 void rxrpc_process_connection(struct work_struct *work)
 262 {
 263         struct rxrpc_connection *conn =
 264                 container_of(work, struct rxrpc_connection, processor);
 265         struct sk_buff *skb;
 266         u32 abort_code = RX_PROTOCOL_ERROR;
 267         int ret;
 268
 269         _enter("{%d}", conn->debug_id);
 270
 271         atomic_inc(&conn->usage);
 272
 273         if (test_and_clear_bit(RXRPC_CONN_CHALLENGE, &conn->events)) {
 274                 rxrpc_secure_connection(conn);
 275                 rxrpc_put_connection(conn);
 276         }
 277
 278         /* go through the conn-level event packets, releasing the ref on this
 279          * connection that each one has when we've finished with it */
 280         while ((skb = skb_dequeue(&conn->rx_queue))) {
 281                 ret = rxrpc_process_event(conn, skb, &abort_code);
 282                 switch (ret) {
 283                 case -EPROTO:
 284                 case -EKEYEXPIRED:
 285                 case -EKEYREJECTED:
 286                         goto protocol_error;
 287                 case -EAGAIN:
 288                         goto requeue_and_leave;
 289                 case -ECONNABORTED:
 290                 default:
 291                         rxrpc_put_connection(conn);
 292                         rxrpc_free_skb(skb);
 293                         break;
 294                 }
 295         }
 296
 297 out:
 298         rxrpc_put_connection(conn);
 299         _leave("");
 300         return;
 301
 302 requeue_and_leave:
 303         skb_queue_head(&conn->rx_queue, skb);
 304         goto out;
 305
 306 protocol_error:
 307         if (rxrpc_abort_connection(conn, -ret, abort_code) < 0)
 308                 goto requeue_and_leave;
 309         rxrpc_put_connection(conn);
 310         rxrpc_free_skb(skb);
 311         _leave(" [EPROTO]");
 312         goto out;
 313 }
 314
 315 /*
 316  * put a packet up for transport-level abort
 317  */
 318 void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb)
 319 {
 320         CHECK_SLAB_OKAY(&local->usage);
 321
 322         if (!atomic_inc_not_zero(&local->usage)) {
 323                 printk("resurrected on reject\n");
 324                 BUG();
 325         }
 326
 327         skb_queue_tail(&local->reject_queue, skb);
 328         rxrpc_queue_work(&local->rejecter);
 329 }
 330
 331 /*
 332  * reject packets through the local endpoint
 333  */
 334 void rxrpc_reject_packets(struct work_struct *work)
 335 {
 336         union {
 337                 struct sockaddr sa;
 338                 struct sockaddr_in sin;
 339         } sa;
 340         struct rxrpc_skb_priv *sp;
 341         struct rxrpc_wire_header whdr;
 342         struct rxrpc_local *local;
 343         struct sk_buff *skb;
 344         struct msghdr msg;
 345         struct kvec iov[2];
 346         size_t size;
 347         __be32 code;
 348
 349         local = container_of(work, struct rxrpc_local, rejecter);
 350         rxrpc_get_local(local);
 351
 352         _enter("%d", local->debug_id);
 353
 354         iov[0].iov_base = &whdr;
 355         iov[0].iov_len = sizeof(whdr);
 356         iov[1].iov_base = &code;
 357         iov[1].iov_len = sizeof(code);
 358         size = sizeof(whdr) + sizeof(code);
 359
 360         msg.msg_name = &sa;
 361         msg.msg_control = NULL;
 362         msg.msg_controllen = 0;
 363         msg.msg_flags = 0;
 364
 365         memset(&sa, 0, sizeof(sa));
 366         sa.sa.sa_family = local->srx.transport.family;
 367         switch (sa.sa.sa_family) {
 368         case AF_INET:
 369                 msg.msg_namelen = sizeof(sa.sin);
 370                 break;
 371         default:
 372                 msg.msg_namelen = 0;
 373                 break;
 374         }
 375
 376         memset(&whdr, 0, sizeof(whdr));
 377         whdr.type = RXRPC_PACKET_TYPE_ABORT;
 378
 379         while ((skb = skb_dequeue(&local->reject_queue))) {
 380                 sp = rxrpc_skb(skb);
 381                 switch (sa.sa.sa_family) {
 382                 case AF_INET:
 383                         sa.sin.sin_port = udp_hdr(skb)->source;
 384                         sa.sin.sin_addr.s_addr = ip_hdr(skb)->saddr;
 385                         code = htonl(skb->priority);
 386
 387                         whdr.epoch      = htonl(sp->hdr.epoch);
 388                         whdr.cid        = htonl(sp->hdr.cid);
 389                         whdr.callNumber = htonl(sp->hdr.callNumber);
 390                         whdr.serviceId  = htons(sp->hdr.serviceId);
 391                         whdr.flags      = sp->hdr.flags;
 392                         whdr.flags      ^= RXRPC_CLIENT_INITIATED;
 393                         whdr.flags      &= RXRPC_CLIENT_INITIATED;
 394
 395                         kernel_sendmsg(local->socket, &msg, iov, 2, size);
 396                         break;
 397
 398                 default:
 399                         break;
 400                 }
 401
 402                 rxrpc_free_skb(skb);
 403                 rxrpc_put_local(local);
 404         }
 405
 406         rxrpc_put_local(local);
 407         _leave("");
 408 }