1 /* 2 * Copyright (C) 2003-2008 Takahiro Hirofuchi 3 * 4 * This is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 17 * USA. 18 */ 19 20 #include <asm/byteorder.h> 21 #include <linux/kthread.h> 22 #include <linux/usb.h> 23 #include <linux/usb/hcd.h> 24 25 #include "usbip_common.h" 26 #include "stub.h" 27 28 static int is_clear_halt_cmd(struct urb *urb) 29 { 30 struct usb_ctrlrequest *req; 31 32 req = (struct usb_ctrlrequest *) urb->setup_packet; 33 34 return (req->bRequest == USB_REQ_CLEAR_FEATURE) && 35 (req->bRequestType == USB_RECIP_ENDPOINT) && 36 (req->wValue == USB_ENDPOINT_HALT); 37 } 38 39 static int is_set_interface_cmd(struct urb *urb) 40 { 41 struct usb_ctrlrequest *req; 42 43 req = (struct usb_ctrlrequest *) urb->setup_packet; 44 45 return (req->bRequest == USB_REQ_SET_INTERFACE) && 46 (req->bRequestType == USB_RECIP_INTERFACE); 47 } 48 49 static int is_set_configuration_cmd(struct urb *urb) 50 { 51 struct usb_ctrlrequest *req; 52 53 req = (struct usb_ctrlrequest *) urb->setup_packet; 54 55 return (req->bRequest == USB_REQ_SET_CONFIGURATION) && 56 (req->bRequestType == USB_RECIP_DEVICE); 57 } 58 59 static int is_reset_device_cmd(struct urb *urb) 60 { 61 struct usb_ctrlrequest *req; 62 __u16 value; 63 __u16 index; 64 65 req = (struct usb_ctrlrequest *) urb->setup_packet; 66 value = le16_to_cpu(req->wValue); 67 index = le16_to_cpu(req->wIndex); 68 69 if ((req->bRequest == USB_REQ_SET_FEATURE) && 70 (req->bRequestType == USB_RT_PORT) && 71 (value == USB_PORT_FEAT_RESET)) { 72 usbip_dbg_stub_rx("reset_device_cmd, port %u\n", index); 73 return 1; 74 } else 75 return 0; 76 } 77 78 static int tweak_clear_halt_cmd(struct urb *urb) 79 { 80 struct usb_ctrlrequest *req; 81 int target_endp; 82 int target_dir; 83 int target_pipe; 84 int ret; 85 86 req = (struct usb_ctrlrequest *) urb->setup_packet; 87 88 /* 89 * The stalled endpoint is specified in the wIndex value. The endpoint 90 * of the urb is the target of this clear_halt request (i.e., control 91 * endpoint). 92 */ 93 target_endp = le16_to_cpu(req->wIndex) & 0x000f; 94 95 /* the stalled endpoint direction is IN or OUT?. USB_DIR_IN is 0x80. */ 96 target_dir = le16_to_cpu(req->wIndex) & 0x0080; 97 98 if (target_dir) 99 target_pipe = usb_rcvctrlpipe(urb->dev, target_endp); 100 else 101 target_pipe = usb_sndctrlpipe(urb->dev, target_endp); 102 103 ret = usb_clear_halt(urb->dev, target_pipe); 104 if (ret < 0) 105 dev_err(&urb->dev->dev, 106 "usb_clear_halt error: devnum %d endp %d ret %d\n", 107 urb->dev->devnum, target_endp, ret); 108 else 109 dev_info(&urb->dev->dev, 110 "usb_clear_halt done: devnum %d endp %d\n", 111 urb->dev->devnum, target_endp); 112 113 return ret; 114 } 115 116 static int tweak_set_interface_cmd(struct urb *urb) 117 { 118 struct usb_ctrlrequest *req; 119 __u16 alternate; 120 __u16 interface; 121 int ret; 122 123 req = (struct usb_ctrlrequest *) urb->setup_packet; 124 alternate = le16_to_cpu(req->wValue); 125 interface = le16_to_cpu(req->wIndex); 126 127 usbip_dbg_stub_rx("set_interface: inf %u alt %u\n", 128 interface, alternate); 129 130 ret = usb_set_interface(urb->dev, interface, alternate); 131 if (ret < 0) 132 dev_err(&urb->dev->dev, 133 "usb_set_interface error: inf %u alt %u ret %d\n", 134 interface, alternate, ret); 135 else 136 dev_info(&urb->dev->dev, 137 "usb_set_interface done: inf %u alt %u\n", 138 interface, alternate); 139 140 return ret; 141 } 142 143 static int tweak_set_configuration_cmd(struct urb *urb) 144 { 145 struct stub_priv *priv = (struct stub_priv *) urb->context; 146 struct stub_device *sdev = priv->sdev; 147 struct usb_ctrlrequest *req; 148 __u16 config; 149 int err; 150 151 req = (struct usb_ctrlrequest *) urb->setup_packet; 152 config = le16_to_cpu(req->wValue); 153 154 err = usb_set_configuration(sdev->udev, config); 155 if (err && err != -ENODEV) 156 dev_err(&sdev->udev->dev, "can't set config #%d, error %d\n", 157 config, err); 158 return 0; 159 } 160 161 static int tweak_reset_device_cmd(struct urb *urb) 162 { 163 struct stub_priv *priv = (struct stub_priv *) urb->context; 164 struct stub_device *sdev = priv->sdev; 165 166 dev_info(&urb->dev->dev, "usb_queue_reset_device\n"); 167 168 if (usb_lock_device_for_reset(sdev->udev, NULL) < 0) { 169 dev_err(&urb->dev->dev, "could not obtain lock to reset device\n"); 170 return 0; 171 } 172 usb_reset_device(sdev->udev); 173 usb_unlock_device(sdev->udev); 174 175 return 0; 176 } 177 178 /* 179 * clear_halt, set_interface, and set_configuration require special tricks. 180 */ 181 static void tweak_special_requests(struct urb *urb) 182 { 183 if (!urb || !urb->setup_packet) 184 return; 185 186 if (usb_pipetype(urb->pipe) != PIPE_CONTROL) 187 return; 188 189 if (is_clear_halt_cmd(urb)) 190 /* tweak clear_halt */ 191 tweak_clear_halt_cmd(urb); 192 193 else if (is_set_interface_cmd(urb)) 194 /* tweak set_interface */ 195 tweak_set_interface_cmd(urb); 196 197 else if (is_set_configuration_cmd(urb)) 198 /* tweak set_configuration */ 199 tweak_set_configuration_cmd(urb); 200 201 else if (is_reset_device_cmd(urb)) 202 tweak_reset_device_cmd(urb); 203 else 204 usbip_dbg_stub_rx("no need to tweak\n"); 205 } 206 207 /* 208 * stub_recv_unlink() unlinks the URB by a call to usb_unlink_urb(). 209 * By unlinking the urb asynchronously, stub_rx can continuously 210 * process coming urbs. Even if the urb is unlinked, its completion 211 * handler will be called and stub_tx will send a return pdu. 212 * 213 * See also comments about unlinking strategy in vhci_hcd.c. 214 */ 215 static int stub_recv_cmd_unlink(struct stub_device *sdev, 216 struct usbip_header *pdu) 217 { 218 int ret; 219 unsigned long flags; 220 struct stub_priv *priv; 221 222 spin_lock_irqsave(&sdev->priv_lock, flags); 223 224 list_for_each_entry(priv, &sdev->priv_init, list) { 225 if (priv->seqnum != pdu->u.cmd_unlink.seqnum) 226 continue; 227 228 dev_info(&priv->urb->dev->dev, "unlink urb %p\n", 229 priv->urb); 230 231 /* 232 * This matched urb is not completed yet (i.e., be in 233 * flight in usb hcd hardware/driver). Now we are 234 * cancelling it. The unlinking flag means that we are 235 * now not going to return the normal result pdu of a 236 * submission request, but going to return a result pdu 237 * of the unlink request. 238 */ 239 priv->unlinking = 1; 240 241 /* 242 * In the case that unlinking flag is on, prev->seqnum 243 * is changed from the seqnum of the cancelling urb to 244 * the seqnum of the unlink request. This will be used 245 * to make the result pdu of the unlink request. 246 */ 247 priv->seqnum = pdu->base.seqnum; 248 249 spin_unlock_irqrestore(&sdev->priv_lock, flags); 250 251 /* 252 * usb_unlink_urb() is now out of spinlocking to avoid 253 * spinlock recursion since stub_complete() is 254 * sometimes called in this context but not in the 255 * interrupt context. If stub_complete() is executed 256 * before we call usb_unlink_urb(), usb_unlink_urb() 257 * will return an error value. In this case, stub_tx 258 * will return the result pdu of this unlink request 259 * though submission is completed and actual unlinking 260 * is not executed. OK? 261 */ 262 /* In the above case, urb->status is not -ECONNRESET, 263 * so a driver in a client host will know the failure 264 * of the unlink request ? 265 */ 266 ret = usb_unlink_urb(priv->urb); 267 if (ret != -EINPROGRESS) 268 dev_err(&priv->urb->dev->dev, 269 "failed to unlink a urb %p, ret %d\n", 270 priv->urb, ret); 271 272 return 0; 273 } 274 275 usbip_dbg_stub_rx("seqnum %d is not pending\n", 276 pdu->u.cmd_unlink.seqnum); 277 278 /* 279 * The urb of the unlink target is not found in priv_init queue. It was 280 * already completed and its results is/was going to be sent by a 281 * CMD_RET pdu. In this case, usb_unlink_urb() is not needed. We only 282 * return the completeness of this unlink request to vhci_hcd. 283 */ 284 stub_enqueue_ret_unlink(sdev, pdu->base.seqnum, 0); 285 286 spin_unlock_irqrestore(&sdev->priv_lock, flags); 287 288 return 0; 289 } 290 291 static int valid_request(struct stub_device *sdev, struct usbip_header *pdu) 292 { 293 struct usbip_device *ud = &sdev->ud; 294 int valid = 0; 295 296 if (pdu->base.devid == sdev->devid) { 297 spin_lock_irq(&ud->lock); 298 if (ud->status == SDEV_ST_USED) { 299 /* A request is valid. */ 300 valid = 1; 301 } 302 spin_unlock_irq(&ud->lock); 303 } 304 305 return valid; 306 } 307 308 static struct stub_priv *stub_priv_alloc(struct stub_device *sdev, 309 struct usbip_header *pdu) 310 { 311 struct stub_priv *priv; 312 struct usbip_device *ud = &sdev->ud; 313 unsigned long flags; 314 315 spin_lock_irqsave(&sdev->priv_lock, flags); 316 317 priv = kmem_cache_zalloc(stub_priv_cache, GFP_ATOMIC); 318 if (!priv) { 319 dev_err(&sdev->udev->dev, "alloc stub_priv\n"); 320 spin_unlock_irqrestore(&sdev->priv_lock, flags); 321 usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC); 322 return NULL; 323 } 324 325 priv->seqnum = pdu->base.seqnum; 326 priv->sdev = sdev; 327 328 /* 329 * After a stub_priv is linked to a list_head, 330 * our error handler can free allocated data. 331 */ 332 list_add_tail(&priv->list, &sdev->priv_init); 333 334 spin_unlock_irqrestore(&sdev->priv_lock, flags); 335 336 return priv; 337 } 338 339 static int get_pipe(struct stub_device *sdev, int epnum, int dir) 340 { 341 struct usb_device *udev = sdev->udev; 342 struct usb_host_endpoint *ep; 343 struct usb_endpoint_descriptor *epd = NULL; 344 345 if (dir == USBIP_DIR_IN) 346 ep = udev->ep_in[epnum & 0x7f]; 347 else 348 ep = udev->ep_out[epnum & 0x7f]; 349 if (!ep) { 350 dev_err(&sdev->udev->dev, "no such endpoint?, %d\n", 351 epnum); 352 BUG(); 353 } 354 355 epd = &ep->desc; 356 if (usb_endpoint_xfer_control(epd)) { 357 if (dir == USBIP_DIR_OUT) 358 return usb_sndctrlpipe(udev, epnum); 359 else 360 return usb_rcvctrlpipe(udev, epnum); 361 } 362 363 if (usb_endpoint_xfer_bulk(epd)) { 364 if (dir == USBIP_DIR_OUT) 365 return usb_sndbulkpipe(udev, epnum); 366 else 367 return usb_rcvbulkpipe(udev, epnum); 368 } 369 370 if (usb_endpoint_xfer_int(epd)) { 371 if (dir == USBIP_DIR_OUT) 372 return usb_sndintpipe(udev, epnum); 373 else 374 return usb_rcvintpipe(udev, epnum); 375 } 376 377 if (usb_endpoint_xfer_isoc(epd)) { 378 if (dir == USBIP_DIR_OUT) 379 return usb_sndisocpipe(udev, epnum); 380 else 381 return usb_rcvisocpipe(udev, epnum); 382 } 383 384 /* NOT REACHED */ 385 dev_err(&sdev->udev->dev, "get pipe, epnum %d\n", epnum); 386 return 0; 387 } 388 389 static void masking_bogus_flags(struct urb *urb) 390 { 391 int xfertype; 392 struct usb_device *dev; 393 struct usb_host_endpoint *ep; 394 int is_out; 395 unsigned int allowed; 396 397 if (!urb || urb->hcpriv || !urb->complete) 398 return; 399 dev = urb->dev; 400 if ((!dev) || (dev->state < USB_STATE_UNAUTHENTICATED)) 401 return; 402 403 ep = (usb_pipein(urb->pipe) ? dev->ep_in : dev->ep_out) 404 [usb_pipeendpoint(urb->pipe)]; 405 if (!ep) 406 return; 407 408 xfertype = usb_endpoint_type(&ep->desc); 409 if (xfertype == USB_ENDPOINT_XFER_CONTROL) { 410 struct usb_ctrlrequest *setup = 411 (struct usb_ctrlrequest *) urb->setup_packet; 412 413 if (!setup) 414 return; 415 is_out = !(setup->bRequestType & USB_DIR_IN) || 416 !setup->wLength; 417 } else { 418 is_out = usb_endpoint_dir_out(&ep->desc); 419 } 420 421 /* enforce simple/standard policy */ 422 allowed = (URB_NO_TRANSFER_DMA_MAP | URB_NO_INTERRUPT | 423 URB_DIR_MASK | URB_FREE_BUFFER); 424 switch (xfertype) { 425 case USB_ENDPOINT_XFER_BULK: 426 if (is_out) 427 allowed |= URB_ZERO_PACKET; 428 /* FALLTHROUGH */ 429 case USB_ENDPOINT_XFER_CONTROL: 430 allowed |= URB_NO_FSBR; /* only affects UHCI */ 431 /* FALLTHROUGH */ 432 default: /* all non-iso endpoints */ 433 if (!is_out) 434 allowed |= URB_SHORT_NOT_OK; 435 break; 436 case USB_ENDPOINT_XFER_ISOC: 437 allowed |= URB_ISO_ASAP; 438 break; 439 } 440 urb->transfer_flags &= allowed; 441 } 442 443 static void stub_recv_cmd_submit(struct stub_device *sdev, 444 struct usbip_header *pdu) 445 { 446 int ret; 447 struct stub_priv *priv; 448 struct usbip_device *ud = &sdev->ud; 449 struct usb_device *udev = sdev->udev; 450 int pipe = get_pipe(sdev, pdu->base.ep, pdu->base.direction); 451 452 priv = stub_priv_alloc(sdev, pdu); 453 if (!priv) 454 return; 455 456 /* setup a urb */ 457 if (usb_pipeisoc(pipe)) 458 priv->urb = usb_alloc_urb(pdu->u.cmd_submit.number_of_packets, 459 GFP_KERNEL); 460 else 461 priv->urb = usb_alloc_urb(0, GFP_KERNEL); 462 463 if (!priv->urb) { 464 dev_err(&udev->dev, "malloc urb\n"); 465 usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC); 466 return; 467 } 468 469 /* allocate urb transfer buffer, if needed */ 470 if (pdu->u.cmd_submit.transfer_buffer_length > 0) { 471 priv->urb->transfer_buffer = 472 kzalloc(pdu->u.cmd_submit.transfer_buffer_length, 473 GFP_KERNEL); 474 if (!priv->urb->transfer_buffer) { 475 usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC); 476 return; 477 } 478 } 479 480 /* copy urb setup packet */ 481 priv->urb->setup_packet = kmemdup(&pdu->u.cmd_submit.setup, 8, 482 GFP_KERNEL); 483 if (!priv->urb->setup_packet) { 484 dev_err(&udev->dev, "allocate setup_packet\n"); 485 usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC); 486 return; 487 } 488 489 /* set other members from the base header of pdu */ 490 priv->urb->context = (void *) priv; 491 priv->urb->dev = udev; 492 priv->urb->pipe = pipe; 493 priv->urb->complete = stub_complete; 494 495 usbip_pack_pdu(pdu, priv->urb, USBIP_CMD_SUBMIT, 0); 496 497 498 if (usbip_recv_xbuff(ud, priv->urb) < 0) 499 return; 500 501 if (usbip_recv_iso(ud, priv->urb) < 0) 502 return; 503 504 /* no need to submit an intercepted request, but harmless? */ 505 tweak_special_requests(priv->urb); 506 507 masking_bogus_flags(priv->urb); 508 /* urb is now ready to submit */ 509 ret = usb_submit_urb(priv->urb, GFP_KERNEL); 510 511 if (ret == 0) 512 usbip_dbg_stub_rx("submit urb ok, seqnum %u\n", 513 pdu->base.seqnum); 514 else { 515 dev_err(&udev->dev, "submit_urb error, %d\n", ret); 516 usbip_dump_header(pdu); 517 usbip_dump_urb(priv->urb); 518 519 /* 520 * Pessimistic. 521 * This connection will be discarded. 522 */ 523 usbip_event_add(ud, SDEV_EVENT_ERROR_SUBMIT); 524 } 525 526 usbip_dbg_stub_rx("Leave\n"); 527 } 528 529 /* recv a pdu */ 530 static void stub_rx_pdu(struct usbip_device *ud) 531 { 532 int ret; 533 struct usbip_header pdu; 534 struct stub_device *sdev = container_of(ud, struct stub_device, ud); 535 struct device *dev = &sdev->udev->dev; 536 537 usbip_dbg_stub_rx("Enter\n"); 538 539 memset(&pdu, 0, sizeof(pdu)); 540 541 /* receive a pdu header */ 542 ret = usbip_recv(ud->tcp_socket, &pdu, sizeof(pdu)); 543 if (ret != sizeof(pdu)) { 544 dev_err(dev, "recv a header, %d\n", ret); 545 usbip_event_add(ud, SDEV_EVENT_ERROR_TCP); 546 return; 547 } 548 549 usbip_header_correct_endian(&pdu, 0); 550 551 if (usbip_dbg_flag_stub_rx) 552 usbip_dump_header(&pdu); 553 554 if (!valid_request(sdev, &pdu)) { 555 dev_err(dev, "recv invalid request\n"); 556 usbip_event_add(ud, SDEV_EVENT_ERROR_TCP); 557 return; 558 } 559 560 switch (pdu.base.command) { 561 case USBIP_CMD_UNLINK: 562 stub_recv_cmd_unlink(sdev, &pdu); 563 break; 564 565 case USBIP_CMD_SUBMIT: 566 stub_recv_cmd_submit(sdev, &pdu); 567 break; 568 569 default: 570 /* NOTREACHED */ 571 dev_err(dev, "unknown pdu\n"); 572 usbip_event_add(ud, SDEV_EVENT_ERROR_TCP); 573 break; 574 } 575 } 576 577 int stub_rx_loop(void *data) 578 { 579 struct usbip_device *ud = data; 580 581 while (!kthread_should_stop()) { 582 if (usbip_event_happened(ud)) 583 break; 584 585 stub_rx_pdu(ud); 586 } 587 588 return 0; 589 } 590