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