1 /* drivers/atm/atmtcp.c - ATM over TCP "device" driver */ 2 3 /* Written 1997-2000 by Werner Almesberger, EPFL LRC/ICA */ 4 5 6 #include <linux/module.h> 7 #include <linux/wait.h> 8 #include <linux/atmdev.h> 9 #include <linux/atm_tcp.h> 10 #include <linux/bitops.h> 11 #include <linux/init.h> 12 #include <linux/slab.h> 13 #include <asm/uaccess.h> 14 #include <linux/atomic.h> 15 16 17 extern int atm_init_aal5(struct atm_vcc *vcc); /* "raw" AAL5 transport */ 18 19 20 #define PRIV(dev) ((struct atmtcp_dev_data *) ((dev)->dev_data)) 21 22 23 struct atmtcp_dev_data { 24 struct atm_vcc *vcc; /* control VCC; NULL if detached */ 25 int persist; /* non-zero if persistent */ 26 }; 27 28 29 #define DEV_LABEL "atmtcp" 30 31 #define MAX_VPI_BITS 8 /* simplifies life */ 32 #define MAX_VCI_BITS 16 33 34 35 /* 36 * Hairy code ahead: the control VCC may be closed while we're still 37 * waiting for an answer, so we need to re-validate out_vcc every once 38 * in a while. 39 */ 40 41 42 static int atmtcp_send_control(struct atm_vcc *vcc,int type, 43 const struct atmtcp_control *msg,int flag) 44 { 45 DECLARE_WAITQUEUE(wait,current); 46 struct atm_vcc *out_vcc; 47 struct sk_buff *skb; 48 struct atmtcp_control *new_msg; 49 int old_test; 50 int error = 0; 51 52 out_vcc = PRIV(vcc->dev) ? PRIV(vcc->dev)->vcc : NULL; 53 if (!out_vcc) return -EUNATCH; 54 skb = alloc_skb(sizeof(*msg),GFP_KERNEL); 55 if (!skb) return -ENOMEM; 56 mb(); 57 out_vcc = PRIV(vcc->dev) ? PRIV(vcc->dev)->vcc : NULL; 58 if (!out_vcc) { 59 dev_kfree_skb(skb); 60 return -EUNATCH; 61 } 62 atm_force_charge(out_vcc,skb->truesize); 63 new_msg = (struct atmtcp_control *) skb_put(skb,sizeof(*new_msg)); 64 *new_msg = *msg; 65 new_msg->hdr.length = ATMTCP_HDR_MAGIC; 66 new_msg->type = type; 67 memset(&new_msg->vcc,0,sizeof(atm_kptr_t)); 68 *(struct atm_vcc **) &new_msg->vcc = vcc; 69 old_test = test_bit(flag,&vcc->flags); 70 out_vcc->push(out_vcc,skb); 71 add_wait_queue(sk_sleep(sk_atm(vcc)), &wait); 72 while (test_bit(flag,&vcc->flags) == old_test) { 73 mb(); 74 out_vcc = PRIV(vcc->dev) ? PRIV(vcc->dev)->vcc : NULL; 75 if (!out_vcc) { 76 error = -EUNATCH; 77 break; 78 } 79 set_current_state(TASK_UNINTERRUPTIBLE); 80 schedule(); 81 } 82 set_current_state(TASK_RUNNING); 83 remove_wait_queue(sk_sleep(sk_atm(vcc)), &wait); 84 return error; 85 } 86 87 88 static int atmtcp_recv_control(const struct atmtcp_control *msg) 89 { 90 struct atm_vcc *vcc = *(struct atm_vcc **) &msg->vcc; 91 92 vcc->vpi = msg->addr.sap_addr.vpi; 93 vcc->vci = msg->addr.sap_addr.vci; 94 vcc->qos = msg->qos; 95 sk_atm(vcc)->sk_err = -msg->result; 96 switch (msg->type) { 97 case ATMTCP_CTRL_OPEN: 98 change_bit(ATM_VF_READY,&vcc->flags); 99 break; 100 case ATMTCP_CTRL_CLOSE: 101 change_bit(ATM_VF_ADDR,&vcc->flags); 102 break; 103 default: 104 printk(KERN_ERR "atmtcp_recv_control: unknown type %d\n", 105 msg->type); 106 return -EINVAL; 107 } 108 wake_up(sk_sleep(sk_atm(vcc))); 109 return 0; 110 } 111 112 113 static void atmtcp_v_dev_close(struct atm_dev *dev) 114 { 115 /* Nothing.... Isn't this simple :-) -- REW */ 116 } 117 118 119 static int atmtcp_v_open(struct atm_vcc *vcc) 120 { 121 struct atmtcp_control msg; 122 int error; 123 short vpi = vcc->vpi; 124 int vci = vcc->vci; 125 126 memset(&msg,0,sizeof(msg)); 127 msg.addr.sap_family = AF_ATMPVC; 128 msg.hdr.vpi = htons(vpi); 129 msg.addr.sap_addr.vpi = vpi; 130 msg.hdr.vci = htons(vci); 131 msg.addr.sap_addr.vci = vci; 132 if (vpi == ATM_VPI_UNSPEC || vci == ATM_VCI_UNSPEC) return 0; 133 msg.type = ATMTCP_CTRL_OPEN; 134 msg.qos = vcc->qos; 135 set_bit(ATM_VF_ADDR,&vcc->flags); 136 clear_bit(ATM_VF_READY,&vcc->flags); /* just in case ... */ 137 error = atmtcp_send_control(vcc,ATMTCP_CTRL_OPEN,&msg,ATM_VF_READY); 138 if (error) return error; 139 return -sk_atm(vcc)->sk_err; 140 } 141 142 143 static void atmtcp_v_close(struct atm_vcc *vcc) 144 { 145 struct atmtcp_control msg; 146 147 memset(&msg,0,sizeof(msg)); 148 msg.addr.sap_family = AF_ATMPVC; 149 msg.addr.sap_addr.vpi = vcc->vpi; 150 msg.addr.sap_addr.vci = vcc->vci; 151 clear_bit(ATM_VF_READY,&vcc->flags); 152 (void) atmtcp_send_control(vcc,ATMTCP_CTRL_CLOSE,&msg,ATM_VF_ADDR); 153 } 154 155 156 static int atmtcp_v_ioctl(struct atm_dev *dev,unsigned int cmd,void __user *arg) 157 { 158 struct atm_cirange ci; 159 struct atm_vcc *vcc; 160 struct sock *s; 161 int i; 162 163 if (cmd != ATM_SETCIRANGE) return -ENOIOCTLCMD; 164 if (copy_from_user(&ci, arg,sizeof(ci))) return -EFAULT; 165 if (ci.vpi_bits == ATM_CI_MAX) ci.vpi_bits = MAX_VPI_BITS; 166 if (ci.vci_bits == ATM_CI_MAX) ci.vci_bits = MAX_VCI_BITS; 167 if (ci.vpi_bits > MAX_VPI_BITS || ci.vpi_bits < 0 || 168 ci.vci_bits > MAX_VCI_BITS || ci.vci_bits < 0) return -EINVAL; 169 read_lock(&vcc_sklist_lock); 170 for(i = 0; i < VCC_HTABLE_SIZE; ++i) { 171 struct hlist_head *head = &vcc_hash[i]; 172 173 sk_for_each(s, head) { 174 vcc = atm_sk(s); 175 if (vcc->dev != dev) 176 continue; 177 if ((vcc->vpi >> ci.vpi_bits) || 178 (vcc->vci >> ci.vci_bits)) { 179 read_unlock(&vcc_sklist_lock); 180 return -EBUSY; 181 } 182 } 183 } 184 read_unlock(&vcc_sklist_lock); 185 dev->ci_range = ci; 186 return 0; 187 } 188 189 190 static int atmtcp_v_send(struct atm_vcc *vcc,struct sk_buff *skb) 191 { 192 struct atmtcp_dev_data *dev_data; 193 struct atm_vcc *out_vcc=NULL; /* Initializer quietens GCC warning */ 194 struct sk_buff *new_skb; 195 struct atmtcp_hdr *hdr; 196 int size; 197 198 if (vcc->qos.txtp.traffic_class == ATM_NONE) { 199 if (vcc->pop) vcc->pop(vcc,skb); 200 else dev_kfree_skb(skb); 201 return -EINVAL; 202 } 203 dev_data = PRIV(vcc->dev); 204 if (dev_data) out_vcc = dev_data->vcc; 205 if (!dev_data || !out_vcc) { 206 if (vcc->pop) vcc->pop(vcc,skb); 207 else dev_kfree_skb(skb); 208 if (dev_data) return 0; 209 atomic_inc(&vcc->stats->tx_err); 210 return -ENOLINK; 211 } 212 size = skb->len+sizeof(struct atmtcp_hdr); 213 new_skb = atm_alloc_charge(out_vcc,size,GFP_ATOMIC); 214 if (!new_skb) { 215 if (vcc->pop) vcc->pop(vcc,skb); 216 else dev_kfree_skb(skb); 217 atomic_inc(&vcc->stats->tx_err); 218 return -ENOBUFS; 219 } 220 hdr = (void *) skb_put(new_skb,sizeof(struct atmtcp_hdr)); 221 hdr->vpi = htons(vcc->vpi); 222 hdr->vci = htons(vcc->vci); 223 hdr->length = htonl(skb->len); 224 skb_copy_from_linear_data(skb, skb_put(new_skb, skb->len), skb->len); 225 if (vcc->pop) vcc->pop(vcc,skb); 226 else dev_kfree_skb(skb); 227 out_vcc->push(out_vcc,new_skb); 228 atomic_inc(&vcc->stats->tx); 229 atomic_inc(&out_vcc->stats->rx); 230 return 0; 231 } 232 233 234 static int atmtcp_v_proc(struct atm_dev *dev,loff_t *pos,char *page) 235 { 236 struct atmtcp_dev_data *dev_data = PRIV(dev); 237 238 if (*pos) return 0; 239 if (!dev_data->persist) return sprintf(page,"ephemeral\n"); 240 return sprintf(page,"persistent, %sconnected\n", 241 dev_data->vcc ? "" : "dis"); 242 } 243 244 245 static void atmtcp_c_close(struct atm_vcc *vcc) 246 { 247 struct atm_dev *atmtcp_dev; 248 struct atmtcp_dev_data *dev_data; 249 250 atmtcp_dev = (struct atm_dev *) vcc->dev_data; 251 dev_data = PRIV(atmtcp_dev); 252 dev_data->vcc = NULL; 253 if (dev_data->persist) return; 254 atmtcp_dev->dev_data = NULL; 255 kfree(dev_data); 256 atm_dev_deregister(atmtcp_dev); 257 vcc->dev_data = NULL; 258 module_put(THIS_MODULE); 259 } 260 261 262 static struct atm_vcc *find_vcc(struct atm_dev *dev, short vpi, int vci) 263 { 264 struct hlist_head *head; 265 struct atm_vcc *vcc; 266 struct sock *s; 267 268 head = &vcc_hash[vci & (VCC_HTABLE_SIZE -1)]; 269 270 sk_for_each(s, head) { 271 vcc = atm_sk(s); 272 if (vcc->dev == dev && 273 vcc->vci == vci && vcc->vpi == vpi && 274 vcc->qos.rxtp.traffic_class != ATM_NONE) { 275 return vcc; 276 } 277 } 278 return NULL; 279 } 280 281 282 static int atmtcp_c_send(struct atm_vcc *vcc,struct sk_buff *skb) 283 { 284 struct atm_dev *dev; 285 struct atmtcp_hdr *hdr; 286 struct atm_vcc *out_vcc; 287 struct sk_buff *new_skb; 288 int result = 0; 289 290 if (!skb->len) return 0; 291 dev = vcc->dev_data; 292 hdr = (struct atmtcp_hdr *) skb->data; 293 if (hdr->length == ATMTCP_HDR_MAGIC) { 294 result = atmtcp_recv_control( 295 (struct atmtcp_control *) skb->data); 296 goto done; 297 } 298 read_lock(&vcc_sklist_lock); 299 out_vcc = find_vcc(dev, ntohs(hdr->vpi), ntohs(hdr->vci)); 300 read_unlock(&vcc_sklist_lock); 301 if (!out_vcc) { 302 result = -EUNATCH; 303 atomic_inc(&vcc->stats->tx_err); 304 goto done; 305 } 306 skb_pull(skb,sizeof(struct atmtcp_hdr)); 307 new_skb = atm_alloc_charge(out_vcc,skb->len,GFP_KERNEL); 308 if (!new_skb) { 309 result = -ENOBUFS; 310 goto done; 311 } 312 __net_timestamp(new_skb); 313 skb_copy_from_linear_data(skb, skb_put(new_skb, skb->len), skb->len); 314 out_vcc->push(out_vcc,new_skb); 315 atomic_inc(&vcc->stats->tx); 316 atomic_inc(&out_vcc->stats->rx); 317 done: 318 if (vcc->pop) vcc->pop(vcc,skb); 319 else dev_kfree_skb(skb); 320 return result; 321 } 322 323 324 /* 325 * Device operations for the virtual ATM devices created by ATMTCP. 326 */ 327 328 329 static struct atmdev_ops atmtcp_v_dev_ops = { 330 .dev_close = atmtcp_v_dev_close, 331 .open = atmtcp_v_open, 332 .close = atmtcp_v_close, 333 .ioctl = atmtcp_v_ioctl, 334 .send = atmtcp_v_send, 335 .proc_read = atmtcp_v_proc, 336 .owner = THIS_MODULE 337 }; 338 339 340 /* 341 * Device operations for the ATMTCP control device. 342 */ 343 344 345 static struct atmdev_ops atmtcp_c_dev_ops = { 346 .close = atmtcp_c_close, 347 .send = atmtcp_c_send 348 }; 349 350 351 static struct atm_dev atmtcp_control_dev = { 352 .ops = &atmtcp_c_dev_ops, 353 .type = "atmtcp", 354 .number = 999, 355 .lock = __SPIN_LOCK_UNLOCKED(atmtcp_control_dev.lock) 356 }; 357 358 359 static int atmtcp_create(int itf,int persist,struct atm_dev **result) 360 { 361 struct atmtcp_dev_data *dev_data; 362 struct atm_dev *dev; 363 364 dev_data = kmalloc(sizeof(*dev_data),GFP_KERNEL); 365 if (!dev_data) 366 return -ENOMEM; 367 368 dev = atm_dev_register(DEV_LABEL,NULL,&atmtcp_v_dev_ops,itf,NULL); 369 if (!dev) { 370 kfree(dev_data); 371 return itf == -1 ? -ENOMEM : -EBUSY; 372 } 373 dev->ci_range.vpi_bits = MAX_VPI_BITS; 374 dev->ci_range.vci_bits = MAX_VCI_BITS; 375 dev->dev_data = dev_data; 376 PRIV(dev)->vcc = NULL; 377 PRIV(dev)->persist = persist; 378 if (result) *result = dev; 379 return 0; 380 } 381 382 383 static int atmtcp_attach(struct atm_vcc *vcc,int itf) 384 { 385 struct atm_dev *dev; 386 387 dev = NULL; 388 if (itf != -1) dev = atm_dev_lookup(itf); 389 if (dev) { 390 if (dev->ops != &atmtcp_v_dev_ops) { 391 atm_dev_put(dev); 392 return -EMEDIUMTYPE; 393 } 394 if (PRIV(dev)->vcc) { 395 atm_dev_put(dev); 396 return -EBUSY; 397 } 398 } 399 else { 400 int error; 401 402 error = atmtcp_create(itf,0,&dev); 403 if (error) return error; 404 } 405 PRIV(dev)->vcc = vcc; 406 vcc->dev = &atmtcp_control_dev; 407 vcc_insert_socket(sk_atm(vcc)); 408 set_bit(ATM_VF_META,&vcc->flags); 409 set_bit(ATM_VF_READY,&vcc->flags); 410 vcc->dev_data = dev; 411 (void) atm_init_aal5(vcc); /* @@@ losing AAL in transit ... */ 412 vcc->stats = &atmtcp_control_dev.stats.aal5; 413 return dev->number; 414 } 415 416 417 static int atmtcp_create_persistent(int itf) 418 { 419 return atmtcp_create(itf,1,NULL); 420 } 421 422 423 static int atmtcp_remove_persistent(int itf) 424 { 425 struct atm_dev *dev; 426 struct atmtcp_dev_data *dev_data; 427 428 dev = atm_dev_lookup(itf); 429 if (!dev) return -ENODEV; 430 if (dev->ops != &atmtcp_v_dev_ops) { 431 atm_dev_put(dev); 432 return -EMEDIUMTYPE; 433 } 434 dev_data = PRIV(dev); 435 if (!dev_data->persist) return 0; 436 dev_data->persist = 0; 437 if (PRIV(dev)->vcc) return 0; 438 kfree(dev_data); 439 atm_dev_put(dev); 440 atm_dev_deregister(dev); 441 return 0; 442 } 443 444 static int atmtcp_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 445 { 446 int err = 0; 447 struct atm_vcc *vcc = ATM_SD(sock); 448 449 if (cmd != SIOCSIFATMTCP && cmd != ATMTCP_CREATE && cmd != ATMTCP_REMOVE) 450 return -ENOIOCTLCMD; 451 452 if (!capable(CAP_NET_ADMIN)) 453 return -EPERM; 454 455 switch (cmd) { 456 case SIOCSIFATMTCP: 457 err = atmtcp_attach(vcc, (int) arg); 458 if (err >= 0) { 459 sock->state = SS_CONNECTED; 460 __module_get(THIS_MODULE); 461 } 462 break; 463 case ATMTCP_CREATE: 464 err = atmtcp_create_persistent((int) arg); 465 break; 466 case ATMTCP_REMOVE: 467 err = atmtcp_remove_persistent((int) arg); 468 break; 469 } 470 return err; 471 } 472 473 static struct atm_ioctl atmtcp_ioctl_ops = { 474 .owner = THIS_MODULE, 475 .ioctl = atmtcp_ioctl, 476 }; 477 478 static __init int atmtcp_init(void) 479 { 480 register_atm_ioctl(&atmtcp_ioctl_ops); 481 return 0; 482 } 483 484 485 static void __exit atmtcp_exit(void) 486 { 487 deregister_atm_ioctl(&atmtcp_ioctl_ops); 488 } 489 490 MODULE_LICENSE("GPL"); 491 module_init(atmtcp_init); 492 module_exit(atmtcp_exit); 493