1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2003-2008 Takahiro Hirofuchi
4  * Copyright (C) 2015-2016 Samsung Electronics
5  *               Krzysztof Opasiak <k.opasiak@samsung.com>
6  */
7 
8 #include <asm/byteorder.h>
9 #include <linux/file.h>
10 #include <linux/fs.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/stat.h>
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <net/sock.h>
17 
18 #include "usbip_common.h"
19 
20 #define DRIVER_AUTHOR "Takahiro Hirofuchi <hirofuchi@users.sourceforge.net>"
21 #define DRIVER_DESC "USB/IP Core"
22 
23 #ifdef CONFIG_USBIP_DEBUG
24 unsigned long usbip_debug_flag = 0xffffffff;
25 #else
26 unsigned long usbip_debug_flag;
27 #endif
28 EXPORT_SYMBOL_GPL(usbip_debug_flag);
29 module_param(usbip_debug_flag, ulong, S_IRUGO|S_IWUSR);
30 MODULE_PARM_DESC(usbip_debug_flag, "debug flags (defined in usbip_common.h)");
31 
32 /* FIXME */
33 struct device_attribute dev_attr_usbip_debug;
34 EXPORT_SYMBOL_GPL(dev_attr_usbip_debug);
35 
usbip_debug_show(struct device * dev,struct device_attribute * attr,char * buf)36 static ssize_t usbip_debug_show(struct device *dev,
37 				struct device_attribute *attr, char *buf)
38 {
39 	return sprintf(buf, "%lx\n", usbip_debug_flag);
40 }
41 
usbip_debug_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)42 static ssize_t usbip_debug_store(struct device *dev,
43 				 struct device_attribute *attr, const char *buf,
44 				 size_t count)
45 {
46 	if (sscanf(buf, "%lx", &usbip_debug_flag) != 1)
47 		return -EINVAL;
48 	return count;
49 }
50 DEVICE_ATTR_RW(usbip_debug);
51 
usbip_dump_buffer(char * buff,int bufflen)52 static void usbip_dump_buffer(char *buff, int bufflen)
53 {
54 	print_hex_dump(KERN_DEBUG, "usbip-core", DUMP_PREFIX_OFFSET, 16, 4,
55 		       buff, bufflen, false);
56 }
57 
usbip_dump_pipe(unsigned int p)58 static void usbip_dump_pipe(unsigned int p)
59 {
60 	unsigned char type = usb_pipetype(p);
61 	unsigned char ep   = usb_pipeendpoint(p);
62 	unsigned char dev  = usb_pipedevice(p);
63 	unsigned char dir  = usb_pipein(p);
64 
65 	pr_debug("dev(%d) ep(%d) [%s] ", dev, ep, dir ? "IN" : "OUT");
66 
67 	switch (type) {
68 	case PIPE_ISOCHRONOUS:
69 		pr_debug("ISO\n");
70 		break;
71 	case PIPE_INTERRUPT:
72 		pr_debug("INT\n");
73 		break;
74 	case PIPE_CONTROL:
75 		pr_debug("CTRL\n");
76 		break;
77 	case PIPE_BULK:
78 		pr_debug("BULK\n");
79 		break;
80 	default:
81 		pr_debug("ERR\n");
82 		break;
83 	}
84 }
85 
usbip_dump_usb_device(struct usb_device * udev)86 static void usbip_dump_usb_device(struct usb_device *udev)
87 {
88 	struct device *dev = &udev->dev;
89 	int i;
90 
91 	dev_dbg(dev, "       devnum(%d) devpath(%s) usb speed(%s)",
92 		udev->devnum, udev->devpath, usb_speed_string(udev->speed));
93 
94 	pr_debug("tt hub ttport %d\n", udev->ttport);
95 
96 	dev_dbg(dev, "                    ");
97 	for (i = 0; i < 16; i++)
98 		pr_debug(" %2u", i);
99 	pr_debug("\n");
100 
101 	dev_dbg(dev, "       toggle0(IN) :");
102 	for (i = 0; i < 16; i++)
103 		pr_debug(" %2u", (udev->toggle[0] & (1 << i)) ? 1 : 0);
104 	pr_debug("\n");
105 
106 	dev_dbg(dev, "       toggle1(OUT):");
107 	for (i = 0; i < 16; i++)
108 		pr_debug(" %2u", (udev->toggle[1] & (1 << i)) ? 1 : 0);
109 	pr_debug("\n");
110 
111 	dev_dbg(dev, "       epmaxp_in   :");
112 	for (i = 0; i < 16; i++) {
113 		if (udev->ep_in[i])
114 			pr_debug(" %2u",
115 			    le16_to_cpu(udev->ep_in[i]->desc.wMaxPacketSize));
116 	}
117 	pr_debug("\n");
118 
119 	dev_dbg(dev, "       epmaxp_out  :");
120 	for (i = 0; i < 16; i++) {
121 		if (udev->ep_out[i])
122 			pr_debug(" %2u",
123 			    le16_to_cpu(udev->ep_out[i]->desc.wMaxPacketSize));
124 	}
125 	pr_debug("\n");
126 
127 	dev_dbg(dev, "parent %s, bus %s\n", dev_name(&udev->parent->dev),
128 		udev->bus->bus_name);
129 
130 	dev_dbg(dev, "have_langid %d, string_langid %d\n",
131 		udev->have_langid, udev->string_langid);
132 
133 	dev_dbg(dev, "maxchild %d\n", udev->maxchild);
134 }
135 
usbip_dump_request_type(__u8 rt)136 static void usbip_dump_request_type(__u8 rt)
137 {
138 	switch (rt & USB_RECIP_MASK) {
139 	case USB_RECIP_DEVICE:
140 		pr_debug("DEVICE");
141 		break;
142 	case USB_RECIP_INTERFACE:
143 		pr_debug("INTERF");
144 		break;
145 	case USB_RECIP_ENDPOINT:
146 		pr_debug("ENDPOI");
147 		break;
148 	case USB_RECIP_OTHER:
149 		pr_debug("OTHER ");
150 		break;
151 	default:
152 		pr_debug("------");
153 		break;
154 	}
155 }
156 
usbip_dump_usb_ctrlrequest(struct usb_ctrlrequest * cmd)157 static void usbip_dump_usb_ctrlrequest(struct usb_ctrlrequest *cmd)
158 {
159 	if (!cmd) {
160 		pr_debug("       : null pointer\n");
161 		return;
162 	}
163 
164 	pr_debug("       ");
165 	pr_debug("bRequestType(%02X) bRequest(%02X) wValue(%04X) wIndex(%04X) wLength(%04X) ",
166 		 cmd->bRequestType, cmd->bRequest,
167 		 cmd->wValue, cmd->wIndex, cmd->wLength);
168 	pr_debug("\n       ");
169 
170 	if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
171 		pr_debug("STANDARD ");
172 		switch (cmd->bRequest) {
173 		case USB_REQ_GET_STATUS:
174 			pr_debug("GET_STATUS\n");
175 			break;
176 		case USB_REQ_CLEAR_FEATURE:
177 			pr_debug("CLEAR_FEAT\n");
178 			break;
179 		case USB_REQ_SET_FEATURE:
180 			pr_debug("SET_FEAT\n");
181 			break;
182 		case USB_REQ_SET_ADDRESS:
183 			pr_debug("SET_ADDRRS\n");
184 			break;
185 		case USB_REQ_GET_DESCRIPTOR:
186 			pr_debug("GET_DESCRI\n");
187 			break;
188 		case USB_REQ_SET_DESCRIPTOR:
189 			pr_debug("SET_DESCRI\n");
190 			break;
191 		case USB_REQ_GET_CONFIGURATION:
192 			pr_debug("GET_CONFIG\n");
193 			break;
194 		case USB_REQ_SET_CONFIGURATION:
195 			pr_debug("SET_CONFIG\n");
196 			break;
197 		case USB_REQ_GET_INTERFACE:
198 			pr_debug("GET_INTERF\n");
199 			break;
200 		case USB_REQ_SET_INTERFACE:
201 			pr_debug("SET_INTERF\n");
202 			break;
203 		case USB_REQ_SYNCH_FRAME:
204 			pr_debug("SYNC_FRAME\n");
205 			break;
206 		default:
207 			pr_debug("REQ(%02X)\n", cmd->bRequest);
208 			break;
209 		}
210 		usbip_dump_request_type(cmd->bRequestType);
211 	} else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) {
212 		pr_debug("CLASS\n");
213 	} else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_VENDOR) {
214 		pr_debug("VENDOR\n");
215 	} else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_RESERVED) {
216 		pr_debug("RESERVED\n");
217 	}
218 }
219 
usbip_dump_urb(struct urb * urb)220 void usbip_dump_urb(struct urb *urb)
221 {
222 	struct device *dev;
223 
224 	if (!urb) {
225 		pr_debug("urb: null pointer!!\n");
226 		return;
227 	}
228 
229 	if (!urb->dev) {
230 		pr_debug("urb->dev: null pointer!!\n");
231 		return;
232 	}
233 
234 	dev = &urb->dev->dev;
235 
236 	usbip_dump_usb_device(urb->dev);
237 
238 	dev_dbg(dev, "   pipe                  :%08x ", urb->pipe);
239 
240 	usbip_dump_pipe(urb->pipe);
241 
242 	dev_dbg(dev, "   status                :%d\n", urb->status);
243 	dev_dbg(dev, "   transfer_flags        :%08X\n", urb->transfer_flags);
244 	dev_dbg(dev, "   transfer_buffer_length:%d\n",
245 						urb->transfer_buffer_length);
246 	dev_dbg(dev, "   actual_length         :%d\n", urb->actual_length);
247 
248 	if (urb->setup_packet && usb_pipetype(urb->pipe) == PIPE_CONTROL)
249 		usbip_dump_usb_ctrlrequest(
250 			(struct usb_ctrlrequest *)urb->setup_packet);
251 
252 	dev_dbg(dev, "   start_frame           :%d\n", urb->start_frame);
253 	dev_dbg(dev, "   number_of_packets     :%d\n", urb->number_of_packets);
254 	dev_dbg(dev, "   interval              :%d\n", urb->interval);
255 	dev_dbg(dev, "   error_count           :%d\n", urb->error_count);
256 }
257 EXPORT_SYMBOL_GPL(usbip_dump_urb);
258 
usbip_dump_header(struct usbip_header * pdu)259 void usbip_dump_header(struct usbip_header *pdu)
260 {
261 	pr_debug("BASE: cmd %u seq %u devid %u dir %u ep %u\n",
262 		 pdu->base.command,
263 		 pdu->base.seqnum,
264 		 pdu->base.devid,
265 		 pdu->base.direction,
266 		 pdu->base.ep);
267 
268 	switch (pdu->base.command) {
269 	case USBIP_CMD_SUBMIT:
270 		pr_debug("USBIP_CMD_SUBMIT: x_flags %u x_len %u sf %u #p %d iv %d\n",
271 			 pdu->u.cmd_submit.transfer_flags,
272 			 pdu->u.cmd_submit.transfer_buffer_length,
273 			 pdu->u.cmd_submit.start_frame,
274 			 pdu->u.cmd_submit.number_of_packets,
275 			 pdu->u.cmd_submit.interval);
276 		break;
277 	case USBIP_CMD_UNLINK:
278 		pr_debug("USBIP_CMD_UNLINK: seq %u\n",
279 			 pdu->u.cmd_unlink.seqnum);
280 		break;
281 	case USBIP_RET_SUBMIT:
282 		pr_debug("USBIP_RET_SUBMIT: st %d al %u sf %d #p %d ec %d\n",
283 			 pdu->u.ret_submit.status,
284 			 pdu->u.ret_submit.actual_length,
285 			 pdu->u.ret_submit.start_frame,
286 			 pdu->u.ret_submit.number_of_packets,
287 			 pdu->u.ret_submit.error_count);
288 		break;
289 	case USBIP_RET_UNLINK:
290 		pr_debug("USBIP_RET_UNLINK: status %d\n",
291 			 pdu->u.ret_unlink.status);
292 		break;
293 	default:
294 		/* NOT REACHED */
295 		pr_err("unknown command\n");
296 		break;
297 	}
298 }
299 EXPORT_SYMBOL_GPL(usbip_dump_header);
300 
301 /* Receive data over TCP/IP. */
usbip_recv(struct socket * sock,void * buf,int size)302 int usbip_recv(struct socket *sock, void *buf, int size)
303 {
304 	int result;
305 	struct kvec iov = {.iov_base = buf, .iov_len = size};
306 	struct msghdr msg = {.msg_flags = MSG_NOSIGNAL};
307 	int total = 0;
308 
309 	if (!sock || !buf || !size)
310 		return -EINVAL;
311 
312 	iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, size);
313 
314 	usbip_dbg_xmit("enter\n");
315 
316 	do {
317 		sock->sk->sk_allocation = GFP_NOIO;
318 
319 		result = sock_recvmsg(sock, &msg, MSG_WAITALL);
320 		if (result <= 0)
321 			goto err;
322 
323 		total += result;
324 	} while (msg_data_left(&msg));
325 
326 	if (usbip_dbg_flag_xmit) {
327 		pr_debug("receiving....\n");
328 		usbip_dump_buffer(buf, size);
329 		pr_debug("received, osize %d ret %d size %zd total %d\n",
330 			 size, result, msg_data_left(&msg), total);
331 	}
332 
333 	return total;
334 
335 err:
336 	return result;
337 }
338 EXPORT_SYMBOL_GPL(usbip_recv);
339 
340 /* there may be more cases to tweak the flags. */
tweak_transfer_flags(unsigned int flags)341 static unsigned int tweak_transfer_flags(unsigned int flags)
342 {
343 	flags &= ~URB_NO_TRANSFER_DMA_MAP;
344 	return flags;
345 }
346 
usbip_pack_cmd_submit(struct usbip_header * pdu,struct urb * urb,int pack)347 static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb,
348 				  int pack)
349 {
350 	struct usbip_header_cmd_submit *spdu = &pdu->u.cmd_submit;
351 
352 	/*
353 	 * Some members are not still implemented in usbip. I hope this issue
354 	 * will be discussed when usbip is ported to other operating systems.
355 	 */
356 	if (pack) {
357 		spdu->transfer_flags =
358 			tweak_transfer_flags(urb->transfer_flags);
359 		spdu->transfer_buffer_length	= urb->transfer_buffer_length;
360 		spdu->start_frame		= urb->start_frame;
361 		spdu->number_of_packets		= urb->number_of_packets;
362 		spdu->interval			= urb->interval;
363 	} else  {
364 		urb->transfer_flags         = spdu->transfer_flags;
365 		urb->transfer_buffer_length = spdu->transfer_buffer_length;
366 		urb->start_frame            = spdu->start_frame;
367 		urb->number_of_packets      = spdu->number_of_packets;
368 		urb->interval               = spdu->interval;
369 	}
370 }
371 
usbip_pack_ret_submit(struct usbip_header * pdu,struct urb * urb,int pack)372 static void usbip_pack_ret_submit(struct usbip_header *pdu, struct urb *urb,
373 				  int pack)
374 {
375 	struct usbip_header_ret_submit *rpdu = &pdu->u.ret_submit;
376 
377 	if (pack) {
378 		rpdu->status		= urb->status;
379 		rpdu->actual_length	= urb->actual_length;
380 		rpdu->start_frame	= urb->start_frame;
381 		rpdu->number_of_packets = urb->number_of_packets;
382 		rpdu->error_count	= urb->error_count;
383 	} else {
384 		urb->status		= rpdu->status;
385 		urb->actual_length	= rpdu->actual_length;
386 		urb->start_frame	= rpdu->start_frame;
387 		urb->number_of_packets = rpdu->number_of_packets;
388 		urb->error_count	= rpdu->error_count;
389 	}
390 }
391 
usbip_pack_pdu(struct usbip_header * pdu,struct urb * urb,int cmd,int pack)392 void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
393 		    int pack)
394 {
395 	switch (cmd) {
396 	case USBIP_CMD_SUBMIT:
397 		usbip_pack_cmd_submit(pdu, urb, pack);
398 		break;
399 	case USBIP_RET_SUBMIT:
400 		usbip_pack_ret_submit(pdu, urb, pack);
401 		break;
402 	default:
403 		/* NOT REACHED */
404 		pr_err("unknown command\n");
405 		break;
406 	}
407 }
408 EXPORT_SYMBOL_GPL(usbip_pack_pdu);
409 
correct_endian_basic(struct usbip_header_basic * base,int send)410 static void correct_endian_basic(struct usbip_header_basic *base, int send)
411 {
412 	if (send) {
413 		base->command	= cpu_to_be32(base->command);
414 		base->seqnum	= cpu_to_be32(base->seqnum);
415 		base->devid	= cpu_to_be32(base->devid);
416 		base->direction	= cpu_to_be32(base->direction);
417 		base->ep	= cpu_to_be32(base->ep);
418 	} else {
419 		base->command	= be32_to_cpu(base->command);
420 		base->seqnum	= be32_to_cpu(base->seqnum);
421 		base->devid	= be32_to_cpu(base->devid);
422 		base->direction	= be32_to_cpu(base->direction);
423 		base->ep	= be32_to_cpu(base->ep);
424 	}
425 }
426 
correct_endian_cmd_submit(struct usbip_header_cmd_submit * pdu,int send)427 static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
428 				      int send)
429 {
430 	if (send) {
431 		pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
432 
433 		cpu_to_be32s(&pdu->transfer_buffer_length);
434 		cpu_to_be32s(&pdu->start_frame);
435 		cpu_to_be32s(&pdu->number_of_packets);
436 		cpu_to_be32s(&pdu->interval);
437 	} else {
438 		pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
439 
440 		be32_to_cpus(&pdu->transfer_buffer_length);
441 		be32_to_cpus(&pdu->start_frame);
442 		be32_to_cpus(&pdu->number_of_packets);
443 		be32_to_cpus(&pdu->interval);
444 	}
445 }
446 
correct_endian_ret_submit(struct usbip_header_ret_submit * pdu,int send)447 static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
448 				      int send)
449 {
450 	if (send) {
451 		cpu_to_be32s(&pdu->status);
452 		cpu_to_be32s(&pdu->actual_length);
453 		cpu_to_be32s(&pdu->start_frame);
454 		cpu_to_be32s(&pdu->number_of_packets);
455 		cpu_to_be32s(&pdu->error_count);
456 	} else {
457 		be32_to_cpus(&pdu->status);
458 		be32_to_cpus(&pdu->actual_length);
459 		be32_to_cpus(&pdu->start_frame);
460 		be32_to_cpus(&pdu->number_of_packets);
461 		be32_to_cpus(&pdu->error_count);
462 	}
463 }
464 
correct_endian_cmd_unlink(struct usbip_header_cmd_unlink * pdu,int send)465 static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
466 				      int send)
467 {
468 	if (send)
469 		pdu->seqnum = cpu_to_be32(pdu->seqnum);
470 	else
471 		pdu->seqnum = be32_to_cpu(pdu->seqnum);
472 }
473 
correct_endian_ret_unlink(struct usbip_header_ret_unlink * pdu,int send)474 static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
475 				      int send)
476 {
477 	if (send)
478 		cpu_to_be32s(&pdu->status);
479 	else
480 		be32_to_cpus(&pdu->status);
481 }
482 
usbip_header_correct_endian(struct usbip_header * pdu,int send)483 void usbip_header_correct_endian(struct usbip_header *pdu, int send)
484 {
485 	__u32 cmd = 0;
486 
487 	if (send)
488 		cmd = pdu->base.command;
489 
490 	correct_endian_basic(&pdu->base, send);
491 
492 	if (!send)
493 		cmd = pdu->base.command;
494 
495 	switch (cmd) {
496 	case USBIP_CMD_SUBMIT:
497 		correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
498 		break;
499 	case USBIP_RET_SUBMIT:
500 		correct_endian_ret_submit(&pdu->u.ret_submit, send);
501 		break;
502 	case USBIP_CMD_UNLINK:
503 		correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
504 		break;
505 	case USBIP_RET_UNLINK:
506 		correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
507 		break;
508 	default:
509 		/* NOT REACHED */
510 		pr_err("unknown command\n");
511 		break;
512 	}
513 }
514 EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
515 
usbip_iso_packet_correct_endian(struct usbip_iso_packet_descriptor * iso,int send)516 static void usbip_iso_packet_correct_endian(
517 		struct usbip_iso_packet_descriptor *iso, int send)
518 {
519 	/* does not need all members. but copy all simply. */
520 	if (send) {
521 		iso->offset	= cpu_to_be32(iso->offset);
522 		iso->length	= cpu_to_be32(iso->length);
523 		iso->status	= cpu_to_be32(iso->status);
524 		iso->actual_length = cpu_to_be32(iso->actual_length);
525 	} else {
526 		iso->offset	= be32_to_cpu(iso->offset);
527 		iso->length	= be32_to_cpu(iso->length);
528 		iso->status	= be32_to_cpu(iso->status);
529 		iso->actual_length = be32_to_cpu(iso->actual_length);
530 	}
531 }
532 
usbip_pack_iso(struct usbip_iso_packet_descriptor * iso,struct usb_iso_packet_descriptor * uiso,int pack)533 static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
534 			   struct usb_iso_packet_descriptor *uiso, int pack)
535 {
536 	if (pack) {
537 		iso->offset		= uiso->offset;
538 		iso->length		= uiso->length;
539 		iso->status		= uiso->status;
540 		iso->actual_length	= uiso->actual_length;
541 	} else {
542 		uiso->offset		= iso->offset;
543 		uiso->length		= iso->length;
544 		uiso->status		= iso->status;
545 		uiso->actual_length	= iso->actual_length;
546 	}
547 }
548 
549 /* must free buffer */
550 struct usbip_iso_packet_descriptor*
usbip_alloc_iso_desc_pdu(struct urb * urb,ssize_t * bufflen)551 usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
552 {
553 	struct usbip_iso_packet_descriptor *iso;
554 	int np = urb->number_of_packets;
555 	ssize_t size = np * sizeof(*iso);
556 	int i;
557 
558 	iso = kzalloc(size, GFP_KERNEL);
559 	if (!iso)
560 		return NULL;
561 
562 	for (i = 0; i < np; i++) {
563 		usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
564 		usbip_iso_packet_correct_endian(&iso[i], 1);
565 	}
566 
567 	*bufflen = size;
568 
569 	return iso;
570 }
571 EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
572 
573 /* some members of urb must be substituted before. */
usbip_recv_iso(struct usbip_device * ud,struct urb * urb)574 int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
575 {
576 	void *buff;
577 	struct usbip_iso_packet_descriptor *iso;
578 	int np = urb->number_of_packets;
579 	int size = np * sizeof(*iso);
580 	int i;
581 	int ret;
582 	int total_length = 0;
583 
584 	if (!usb_pipeisoc(urb->pipe))
585 		return 0;
586 
587 	/* my Bluetooth dongle gets ISO URBs which are np = 0 */
588 	if (np == 0)
589 		return 0;
590 
591 	buff = kzalloc(size, GFP_KERNEL);
592 	if (!buff)
593 		return -ENOMEM;
594 
595 	ret = usbip_recv(ud->tcp_socket, buff, size);
596 	if (ret != size) {
597 		dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
598 			ret);
599 		kfree(buff);
600 
601 		if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
602 			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
603 		else
604 			usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
605 
606 		return -EPIPE;
607 	}
608 
609 	iso = (struct usbip_iso_packet_descriptor *) buff;
610 	for (i = 0; i < np; i++) {
611 		usbip_iso_packet_correct_endian(&iso[i], 0);
612 		usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
613 		total_length += urb->iso_frame_desc[i].actual_length;
614 	}
615 
616 	kfree(buff);
617 
618 	if (total_length != urb->actual_length) {
619 		dev_err(&urb->dev->dev,
620 			"total length of iso packets %d not equal to actual length of buffer %d\n",
621 			total_length, urb->actual_length);
622 
623 		if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
624 			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
625 		else
626 			usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
627 
628 		return -EPIPE;
629 	}
630 
631 	return ret;
632 }
633 EXPORT_SYMBOL_GPL(usbip_recv_iso);
634 
635 /*
636  * This functions restores the padding which was removed for optimizing
637  * the bandwidth during transfer over tcp/ip
638  *
639  * buffer and iso packets need to be stored and be in propeper endian in urb
640  * before calling this function
641  */
usbip_pad_iso(struct usbip_device * ud,struct urb * urb)642 void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
643 {
644 	int np = urb->number_of_packets;
645 	int i;
646 	int actualoffset = urb->actual_length;
647 
648 	if (!usb_pipeisoc(urb->pipe))
649 		return;
650 
651 	/* if no packets or length of data is 0, then nothing to unpack */
652 	if (np == 0 || urb->actual_length == 0)
653 		return;
654 
655 	/*
656 	 * if actual_length is transfer_buffer_length then no padding is
657 	 * present.
658 	 */
659 	if (urb->actual_length == urb->transfer_buffer_length)
660 		return;
661 
662 	/*
663 	 * loop over all packets from last to first (to prevent overwriting
664 	 * memory when padding) and move them into the proper place
665 	 */
666 	for (i = np-1; i > 0; i--) {
667 		actualoffset -= urb->iso_frame_desc[i].actual_length;
668 		memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
669 			urb->transfer_buffer + actualoffset,
670 			urb->iso_frame_desc[i].actual_length);
671 	}
672 }
673 EXPORT_SYMBOL_GPL(usbip_pad_iso);
674 
675 /* some members of urb must be substituted before. */
usbip_recv_xbuff(struct usbip_device * ud,struct urb * urb)676 int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
677 {
678 	struct scatterlist *sg;
679 	int ret = 0;
680 	int recv;
681 	int size;
682 	int copy;
683 	int i;
684 
685 	if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
686 		/* the direction of urb must be OUT. */
687 		if (usb_pipein(urb->pipe))
688 			return 0;
689 
690 		size = urb->transfer_buffer_length;
691 	} else {
692 		/* the direction of urb must be IN. */
693 		if (usb_pipeout(urb->pipe))
694 			return 0;
695 
696 		size = urb->actual_length;
697 	}
698 
699 	/* no need to recv xbuff */
700 	if (!(size > 0))
701 		return 0;
702 
703 	if (size > urb->transfer_buffer_length)
704 		/* should not happen, probably malicious packet */
705 		goto error;
706 
707 	if (urb->num_sgs) {
708 		copy = size;
709 		for_each_sg(urb->sg, sg, urb->num_sgs, i) {
710 			int recv_size;
711 
712 			if (copy < sg->length)
713 				recv_size = copy;
714 			else
715 				recv_size = sg->length;
716 
717 			recv = usbip_recv(ud->tcp_socket, sg_virt(sg),
718 						recv_size);
719 
720 			if (recv != recv_size)
721 				goto error;
722 
723 			copy -= recv;
724 			ret += recv;
725 
726 			if (!copy)
727 				break;
728 		}
729 
730 		if (ret != size)
731 			goto error;
732 	} else {
733 		ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
734 		if (ret != size)
735 			goto error;
736 	}
737 
738 	return ret;
739 
740 error:
741 	dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
742 	if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
743 		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
744 	else
745 		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
746 
747 	return -EPIPE;
748 }
749 EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
750 
usbip_core_init(void)751 static int __init usbip_core_init(void)
752 {
753 	return usbip_init_eh();
754 }
755 
usbip_core_exit(void)756 static void __exit usbip_core_exit(void)
757 {
758 	usbip_finish_eh();
759 	return;
760 }
761 
762 module_init(usbip_core_init);
763 module_exit(usbip_core_exit);
764 
765 MODULE_AUTHOR(DRIVER_AUTHOR);
766 MODULE_DESCRIPTION(DRIVER_DESC);
767 MODULE_LICENSE("GPL");
768