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