net/atm/svc.c

   1 /* net/atm/svc.c - ATM SVC sockets */
   2
   3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   4
   5
   6 #include <linux/string.h>
   7 #include <linux/net.h>          /* struct socket, struct net_proto,
   8                                    struct proto_ops */
   9 #include <linux/errno.h>        /* error codes */
  10 #include <linux/kernel.h>       /* printk */
  11 #include <linux/skbuff.h>
  12 #include <linux/wait.h>
  13 #include <linux/sched.h>        /* jiffies and HZ */
  14 #include <linux/fcntl.h>        /* O_NONBLOCK */
  15 #include <linux/init.h>
  16 #include <linux/atm.h>          /* ATM stuff */
  17 #include <linux/atmsap.h>
  18 #include <linux/atmsvc.h>
  19 #include <linux/atmdev.h>
  20 #include <linux/bitops.h>
  21 #include <net/sock.h>           /* for sock_no_* */
  22 #include <asm/uaccess.h>
  23
  24 #include "resources.h"
  25 #include "common.h"             /* common for PVCs and SVCs */
  26 #include "signaling.h"
  27 #include "addr.h"
  28
  29
  30 #if 0
  31 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  32 #else
  33 #define DPRINTK(format,args...)
  34 #endif
  35
  36
  37 static int svc_create(struct socket *sock,int protocol);
  38
  39
  40 /*
  41  * Note: since all this is still nicely synchronized with the signaling demon,
  42  *       there's no need to protect sleep loops with clis. If signaling is
  43  *       moved into the kernel, that would change.
  44  */
  45
  46
  47 void svc_callback(struct atm_vcc *vcc)
  48 {
  49         wake_up(&vcc->sleep);
  50 }
  51
  52
  53
  54
  55 static int svc_shutdown(struct socket *sock,int how)
  56 {
  57         return 0;
  58 }
  59
  60
  61 static void svc_disconnect(struct atm_vcc *vcc)
  62 {
  63         DECLARE_WAITQUEUE(wait,current);
  64         struct sk_buff *skb;
  65
  66         DPRINTK("svc_disconnect %p\n",vcc);
  67         if (test_bit(ATM_VF_REGIS,&vcc->flags)) {
  68                 add_wait_queue(&vcc->sleep,&wait);
  69                 sigd_enq(vcc,as_close,NULL,NULL,NULL);
  70                 while (!test_bit(ATM_VF_RELEASED,&vcc->flags) && sigd) {
  71                         set_current_state(TASK_UNINTERRUPTIBLE);
  72                         schedule();
  73                 }
  74                 remove_wait_queue(&vcc->sleep,&wait);
  75         }
  76         /* beware - socket is still in use by atmsigd until the last
  77            as_indicate has been answered */
  78         while ((skb = skb_dequeue(&vcc->sk->receive_queue))) {
  79                 DPRINTK("LISTEN REL\n");
  80                 sigd_enq2(NULL,as_reject,vcc,NULL,NULL,&vcc->qos,0);
  81                 dev_kfree_skb(skb);
  82         }
  83         clear_bit(ATM_VF_REGIS,&vcc->flags);
  84         clear_bit(ATM_VF_RELEASED,&vcc->flags);
  85         clear_bit(ATM_VF_CLOSE,&vcc->flags);
  86         /* ... may retry later */
  87 }
  88
  89
  90 static int svc_release(struct socket *sock)
  91 {
  92         struct sock *sk = sock->sk;
  93         struct atm_vcc *vcc;
  94
  95         if (sk)  {
  96                 vcc = ATM_SD(sock);
  97                 DPRINTK("svc_release %p\n", vcc);
  98                 clear_bit(ATM_VF_READY, &vcc->flags);
  99                 /* VCC pointer is used as a reference, so we must not free it
 100                    (thereby subjecting it to re-use) before all pending connections
 101                    are closed */
 102                 sock_hold(sk);
 103                 vcc_release(sock);
 104                 svc_disconnect(vcc);
 105                 sock_put(sk);
 106         }
 107         return 0;
 108 }
 109
 110
 111 static int svc_bind(struct socket *sock,struct sockaddr *sockaddr,
 112     int sockaddr_len)
 113 {
 114         DECLARE_WAITQUEUE(wait,current);
 115         struct sock *sk = sock->sk;
 116         struct sockaddr_atmsvc *addr;
 117         struct atm_vcc *vcc;
 118         int error;
 119
 120         if (sockaddr_len != sizeof(struct sockaddr_atmsvc))
 121                 return -EINVAL;
 122         lock_sock(sk);
 123         if (sock->state == SS_CONNECTED) {
 124                 error = -EISCONN;
 125                 goto out;
 126         }
 127         if (sock->state != SS_UNCONNECTED) {
 128                 error = -EINVAL;
 129                 goto out;
 130         }
 131         vcc = ATM_SD(sock);
 132         if (test_bit(ATM_VF_SESSION, &vcc->flags)) {
 133                 error = -EINVAL;
 134                 goto out;
 135         }
 136         addr = (struct sockaddr_atmsvc *) sockaddr;
 137         if (addr->sas_family != AF_ATMSVC) {
 138                 error = -EAFNOSUPPORT;
 139                 goto out;
 140         }
 141         clear_bit(ATM_VF_BOUND,&vcc->flags);
 142             /* failing rebind will kill old binding */
 143         /* @@@ check memory (de)allocation on rebind */
 144         if (!test_bit(ATM_VF_HASQOS,&vcc->flags)) {
 145                 error = -EBADFD;
 146                 goto out;
 147         }
 148         vcc->local = *addr;
 149         vcc->reply = WAITING;
 150         add_wait_queue(&vcc->sleep,&wait);
 151         sigd_enq(vcc,as_bind,NULL,NULL,&vcc->local);
 152         while (vcc->reply == WAITING && sigd) {
 153                 set_current_state(TASK_UNINTERRUPTIBLE);
 154                 schedule();
 155         }
 156         remove_wait_queue(&vcc->sleep,&wait);
 157         clear_bit(ATM_VF_REGIS,&vcc->flags); /* doesn't count */
 158         if (!sigd) {
 159                 error = -EUNATCH;
 160                 goto out;
 161         }
 162         if (!vcc->reply)
 163                 set_bit(ATM_VF_BOUND,&vcc->flags);
 164         error = vcc->reply;
 165 out:
 166         release_sock(sk);
 167         return error;
 168 }
 169
 170
 171 static int svc_connect(struct socket *sock,struct sockaddr *sockaddr,
 172     int sockaddr_len,int flags)
 173 {
 174         DECLARE_WAITQUEUE(wait,current);
 175         struct sock *sk = sock->sk;
 176         struct sockaddr_atmsvc *addr;
 177         struct atm_vcc *vcc = ATM_SD(sock);
 178         int error;
 179
 180         DPRINTK("svc_connect %p\n",vcc);
 181         lock_sock(sk);
 182         if (sockaddr_len != sizeof(struct sockaddr_atmsvc)) {
 183                 error = -EINVAL;
 184                 goto out;
 185         }
 186
 187         switch (sock->state) {
 188         default:
 189                 error = -EINVAL;
 190                 goto out;
 191         case SS_CONNECTED:
 192                 error = -EISCONN;
 193                 goto out;
 194         case SS_CONNECTING:
 195                 if (vcc->reply == WAITING) {
 196                         error = -EALREADY;
 197                         goto out;
 198                 }
 199                 sock->state = SS_UNCONNECTED;
 200                 if (vcc->reply) {
 201                         error = vcc->reply;
 202                         goto out;
 203                 }
 204                 break;
 205         case SS_UNCONNECTED:
 206                 if (test_bit(ATM_VF_SESSION, &vcc->flags)) {
 207                         error = -EINVAL;
 208                         goto out;
 209                 }
 210                 addr = (struct sockaddr_atmsvc *) sockaddr;
 211                 if (addr->sas_family != AF_ATMSVC) {
 212                         error = -EAFNOSUPPORT;
 213                         goto out;
 214                 }
 215                 if (!test_bit(ATM_VF_HASQOS, &vcc->flags)) {
 216                         error = -EBADFD;
 217                         goto out;
 218                 }
 219                 if (vcc->qos.txtp.traffic_class == ATM_ANYCLASS ||
 220                     vcc->qos.rxtp.traffic_class == ATM_ANYCLASS) {
 221                         error = -EINVAL;
 222                         goto out;
 223                 }
 224                 if (!vcc->qos.txtp.traffic_class &&
 225                     !vcc->qos.rxtp.traffic_class) {
 226                         error = -EINVAL;
 227                         goto out;
 228                 }
 229                 vcc->remote = *addr;
 230                 vcc->reply = WAITING;
 231                 add_wait_queue(&vcc->sleep,&wait);
 232                 sigd_enq(vcc,as_connect,NULL,NULL,&vcc->remote);
 233                 if (flags & O_NONBLOCK) {
 234                         remove_wait_queue(&vcc->sleep,&wait);
 235                         sock->state = SS_CONNECTING;
 236                         error = -EINPROGRESS;
 237                         goto out;
 238                 }
 239                 error = 0;
 240                 while (vcc->reply == WAITING && sigd) {
 241                         set_current_state(TASK_INTERRUPTIBLE);
 242                         schedule();
 243                         if (!signal_pending(current)) continue;
 244                         DPRINTK("*ABORT*\n");
 245                         /*
 246                          * This is tricky:
 247                          *   Kernel ---close--> Demon
 248                          *   Kernel <--close--- Demon
 249                          * or
 250                          *   Kernel ---close--> Demon
 251                          *   Kernel <--error--- Demon
 252                          * or
 253                          *   Kernel ---close--> Demon
 254                          *   Kernel <--okay---- Demon
 255                          *   Kernel <--close--- Demon
 256                          */
 257                         sigd_enq(vcc,as_close,NULL,NULL,NULL);
 258                         while (vcc->reply == WAITING && sigd) {
 259                                 set_current_state(TASK_UNINTERRUPTIBLE);
 260                                 schedule();
 261                         }
 262                         if (!vcc->reply)
 263                                 while (!test_bit(ATM_VF_RELEASED,&vcc->flags)
 264                                     && sigd) {
 265                                         set_current_state(TASK_UNINTERRUPTIBLE);
 266                                         schedule();
 267                                 }
 268                         clear_bit(ATM_VF_REGIS,&vcc->flags);
 269                         clear_bit(ATM_VF_RELEASED,&vcc->flags);
 270                         clear_bit(ATM_VF_CLOSE,&vcc->flags);
 271                             /* we're gone now but may connect later */
 272                         error = -EINTR;
 273                         break;
 274                 }
 275                 remove_wait_queue(&vcc->sleep,&wait);
 276                 if (error)
 277                         goto out;
 278                 if (!sigd) {
 279                         error = -EUNATCH;
 280                         goto out;
 281                 }
 282                 if (vcc->reply) {
 283                         error = vcc->reply;
 284                         goto out;
 285                 }
 286         }
 287 /*
 288  * Not supported yet
 289  *
 290  * #ifndef CONFIG_SINGLE_SIGITF
 291  */
 292         vcc->qos.txtp.max_pcr = SELECT_TOP_PCR(vcc->qos.txtp);
 293         vcc->qos.txtp.pcr = 0;
 294         vcc->qos.txtp.min_pcr = 0;
 295 /*
 296  * #endif
 297  */
 298         if (!(error = vcc_connect(sock, vcc->itf, vcc->vpi, vcc->vci)))
 299                 sock->state = SS_CONNECTED;
 300         else (void) svc_disconnect(vcc);
 301 out:
 302         release_sock(sk);
 303         return error;
 304 }
 305
 306
 307 static int svc_listen(struct socket *sock,int backlog)
 308 {
 309         DECLARE_WAITQUEUE(wait,current);
 310         struct sock *sk = sock->sk;
 311         struct atm_vcc *vcc = ATM_SD(sock);
 312         int error;
 313
 314         DPRINTK("svc_listen %p\n",vcc);
 315         lock_sock(sk);
 316         /* let server handle listen on unbound sockets */
 317         if (test_bit(ATM_VF_SESSION,&vcc->flags)) {
 318                 error = -EINVAL;
 319                 goto out;
 320         }
 321         vcc->reply = WAITING;
 322         add_wait_queue(&vcc->sleep,&wait);
 323         sigd_enq(vcc,as_listen,NULL,NULL,&vcc->local);
 324         while (vcc->reply == WAITING && sigd) {
 325                 set_current_state(TASK_UNINTERRUPTIBLE);
 326                 schedule();
 327         }
 328         remove_wait_queue(&vcc->sleep,&wait);
 329         if (!sigd) {
 330                 error = -EUNATCH;
 331                 goto out;
 332         }
 333         set_bit(ATM_VF_LISTEN,&vcc->flags);
 334         vcc->sk->max_ack_backlog = backlog > 0 ? backlog : ATM_BACKLOG_DEFAULT;
 335         error = vcc->reply;
 336 out:
 337         release_sock(sk);
 338         return error;
 339 }
 340
 341
 342 static int svc_accept(struct socket *sock,struct socket *newsock,int flags)
 343 {
 344         struct sock *sk = sock->sk;
 345         struct sk_buff *skb;
 346         struct atmsvc_msg *msg;
 347         struct atm_vcc *old_vcc = ATM_SD(sock);
 348         struct atm_vcc *new_vcc;
 349         int error;
 350
 351         lock_sock(sk);
 352
 353         error = svc_create(newsock,0);
 354         if (error)
 355                 goto out;
 356
 357         new_vcc = ATM_SD(newsock);
 358
 359         DPRINTK("svc_accept %p -> %p\n",old_vcc,new_vcc);
 360         while (1) {
 361                 DECLARE_WAITQUEUE(wait,current);
 362
 363                 add_wait_queue(&old_vcc->sleep,&wait);
 364                 while (!(skb = skb_dequeue(&old_vcc->sk->receive_queue)) && sigd) {
 365                         if (test_bit(ATM_VF_RELEASED,&old_vcc->flags)) break;
 366                         if (test_bit(ATM_VF_CLOSE,&old_vcc->flags)) {
 367                                 error = old_vcc->reply;
 368                                 break;
 369                         }
 370                         if (flags & O_NONBLOCK) {
 371                                 error = -EAGAIN;
 372                                 break;
 373                         }
 374                         release_sock(sk);
 375                         schedule();
 376                         lock_sock(sk);
 377                         if (signal_pending(current)) {
 378                                 error = -ERESTARTSYS;
 379                                 break;
 380                         }
 381                 }
 382                 remove_wait_queue(&old_vcc->sleep,&wait);
 383                 if (error)
 384                         goto out;
 385                 if (!skb) {
 386                         error = -EUNATCH;
 387                         goto out;
 388                 }
 389                 msg = (struct atmsvc_msg *) skb->data;
 390                 new_vcc->qos = msg->qos;
 391                 set_bit(ATM_VF_HASQOS,&new_vcc->flags);
 392                 new_vcc->remote = msg->svc;
 393                 new_vcc->local = msg->local;
 394                 new_vcc->sap = msg->sap;
 395                 error = vcc_connect(newsock, msg->pvc.sap_addr.itf,
 396                                     msg->pvc.sap_addr.vpi, msg->pvc.sap_addr.vci);
 397                 dev_kfree_skb(skb);
 398                 old_vcc->sk->ack_backlog--;
 399                 if (error) {
 400                         sigd_enq2(NULL,as_reject,old_vcc,NULL,NULL,
 401                             &old_vcc->qos,error);
 402                         error = error == -EAGAIN ? -EBUSY : error;
 403                         goto out;
 404                 }
 405                 /* wait should be short, so we ignore the non-blocking flag */
 406                 new_vcc->reply = WAITING;
 407                 add_wait_queue(&new_vcc->sleep,&wait);
 408                 sigd_enq(new_vcc,as_accept,old_vcc,NULL,NULL);
 409                 while (new_vcc->reply == WAITING && sigd) {
 410                         set_current_state(TASK_UNINTERRUPTIBLE);
 411                         release_sock(sk);
 412                         schedule();
 413                         lock_sock(sk);
 414                 }
 415                 remove_wait_queue(&new_vcc->sleep,&wait);
 416                 if (!sigd) {
 417                         error = -EUNATCH;
 418                         goto out;
 419                 }
 420                 if (!new_vcc->reply) break;
 421                 if (new_vcc->reply != -ERESTARTSYS) {
 422                         error = new_vcc->reply;
 423                         goto out;
 424                 }
 425         }
 426         newsock->state = SS_CONNECTED;
 427 out:
 428         release_sock(sk);
 429         return error;
 430 }
 431
 432
 433 static int svc_getname(struct socket *sock,struct sockaddr *sockaddr,
 434     int *sockaddr_len,int peer)
 435 {
 436         struct sockaddr_atmsvc *addr;
 437
 438         *sockaddr_len = sizeof(struct sockaddr_atmsvc);
 439         addr = (struct sockaddr_atmsvc *) sockaddr;
 440         memcpy(addr,peer ? &ATM_SD(sock)->remote : &ATM_SD(sock)->local,
 441             sizeof(struct sockaddr_atmsvc));
 442         return 0;
 443 }
 444
 445
 446 int svc_change_qos(struct atm_vcc *vcc,struct atm_qos *qos)
 447 {
 448         DECLARE_WAITQUEUE(wait,current);
 449
 450         vcc->reply = WAITING;
 451         add_wait_queue(&vcc->sleep,&wait);
 452         sigd_enq2(vcc,as_modify,NULL,NULL,&vcc->local,qos,0);
 453         while (vcc->reply == WAITING && !test_bit(ATM_VF_RELEASED,&vcc->flags)
 454             && sigd) {
 455                 set_current_state(TASK_UNINTERRUPTIBLE);
 456                 schedule();
 457         }
 458         remove_wait_queue(&vcc->sleep,&wait);
 459         if (!sigd) return -EUNATCH;
 460         return vcc->reply;
 461 }
 462
 463
 464 static int svc_setsockopt(struct socket *sock,int level,int optname,
 465     char *optval,int optlen)
 466 {
 467         struct sock *sk = sock->sk;
 468         struct atm_vcc *vcc;
 469         int error = 0;
 470
 471         if (!__SO_LEVEL_MATCH(optname, level) || optname != SO_ATMSAP ||
 472             optlen != sizeof(struct atm_sap)) {
 473                 error = vcc_setsockopt(sock, level, optname, optval, optlen);
 474                 goto out;
 475         }
 476         vcc = ATM_SD(sock);
 477         if (copy_from_user(&vcc->sap, optval, optlen)) {
 478                 error = -EFAULT;
 479                 goto out;
 480         }
 481         set_bit(ATM_VF_HASSAP, &vcc->flags);
 482 out:
 483         release_sock(sk);
 484         return error;
 485 }
 486
 487
 488 static int svc_getsockopt(struct socket *sock,int level,int optname,
 489     char *optval,int *optlen)
 490 {
 491         struct sock *sk = sock->sk;
 492         int error = 0, len;
 493
 494         lock_sock(sk);
 495         if (!__SO_LEVEL_MATCH(optname, level) || optname != SO_ATMSAP) {
 496                 error = vcc_getsockopt(sock, level, optname, optval, optlen);
 497                 goto out;
 498         }
 499         if (get_user(len, optlen)) {
 500                 error = -EFAULT;
 501                 goto out;
 502         }
 503         if (len != sizeof(struct atm_sap)) {
 504                 error = -EINVAL;
 505                 goto out;
 506         }
 507         if (copy_to_user(optval, &ATM_SD(sock)->sap, sizeof(struct atm_sap))) {
 508                 error = -EFAULT;
 509                 goto out;
 510         }
 511 out:
 512         release_sock(sk);
 513         return error;
 514 }
 515
 516
 517 static struct proto_ops svc_proto_ops = {
 518         .family =       PF_ATMSVC,
 519
 520         .release =      svc_release,
 521         .bind =         svc_bind,
 522         .connect =      svc_connect,
 523         .socketpair =   sock_no_socketpair,
 524         .accept =       svc_accept,
 525         .getname =      svc_getname,
 526         .poll =         atm_poll,
 527         .ioctl =        vcc_ioctl,
 528         .listen =       svc_listen,
 529         .shutdown =     svc_shutdown,
 530         .setsockopt =   svc_setsockopt,
 531         .getsockopt =   svc_getsockopt,
 532         .sendmsg =      vcc_sendmsg,
 533         .recvmsg =      vcc_recvmsg,
 534         .mmap =         sock_no_mmap,
 535         .sendpage =     sock_no_sendpage,
 536 };
 537
 538
 539 static int svc_create(struct socket *sock,int protocol)
 540 {
 541         int error;
 542
 543         sock->ops = &svc_proto_ops;
 544         error = vcc_create(sock, protocol, AF_ATMSVC);
 545         if (error) return error;
 546         ATM_SD(sock)->callback = svc_callback;
 547         ATM_SD(sock)->local.sas_family = AF_ATMSVC;
 548         ATM_SD(sock)->remote.sas_family = AF_ATMSVC;
 549         return 0;
 550 }
 551
 552
 553 static struct net_proto_family svc_family_ops = {
 554         PF_ATMSVC,
 555         svc_create,
 556         0,                      /* no authentication */
 557         0,                      /* no encryption */
 558         0                       /* no encrypt_net */
 559 };
 560
 561
 562 /*
 563  *      Initialize the ATM SVC protocol family
 564  */
 565
 566 int atmsvc_init(void)
 567 {
 568         return sock_register(&svc_family_ops);
 569 }
 570
 571 void atmsvc_exit(void)
 572 {
 573         sock_unregister(PF_ATMSVC);
 574 }