1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * f_rndis.c -- RNDIS link function driver 4 * 5 * Copyright (C) 2003-2005,2008 David Brownell 6 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger 7 * Copyright (C) 2008 Nokia Corporation 8 * Copyright (C) 2009 Samsung Electronics 9 * Author: Michal Nazarewicz (mina86@mina86.com) 10 */ 11 12/* #define VERBOSE_DEBUG */ 13 14#include <linux/slab.h> 15#include <linux/kernel.h> 16#include <linux/module.h> 17#include <linux/device.h> 18#include <linux/etherdevice.h> 19 20#include <linux/atomic.h> 21 22#include "u_ether.h" 23#include "u_ether_configfs.h" 24#include "u_rndis.h" 25#include "rndis.h" 26#include "configfs.h" 27 28/* 29 * This function is an RNDIS Ethernet port -- a Microsoft protocol that's 30 * been promoted instead of the standard CDC Ethernet. The published RNDIS 31 * spec is ambiguous, incomplete, and needlessly complex. Variants such as 32 * ActiveSync have even worse status in terms of specification. 33 * 34 * In short: it's a protocol controlled by (and for) Microsoft, not for an 35 * Open ecosystem or markets. Linux supports it *only* because Microsoft 36 * doesn't support the CDC Ethernet standard. 37 * 38 * The RNDIS data transfer model is complex, with multiple Ethernet packets 39 * per USB message, and out of band data. The control model is built around 40 * what's essentially an "RNDIS RPC" protocol. It's all wrapped in a CDC ACM 41 * (modem, not Ethernet) veneer, with those ACM descriptors being entirely 42 * useless (they're ignored). RNDIS expects to be the only function in its 43 * configuration, so it's no real help if you need composite devices; and 44 * it expects to be the first configuration too. 45 * 46 * There is a single technical advantage of RNDIS over CDC Ethernet, if you 47 * discount the fluff that its RPC can be made to deliver: it doesn't need 48 * a NOP altsetting for the data interface. That lets it work on some of the 49 * "so smart it's stupid" hardware which takes over configuration changes 50 * from the software, and adds restrictions like "no altsettings". 51 * 52 * Unfortunately MSFT's RNDIS drivers are buggy. They hang or oops, and 53 * have all sorts of contrary-to-specification oddities that can prevent 54 * them from working sanely. Since bugfixes (or accurate specs, letting 55 * Linux work around those bugs) are unlikely to ever come from MSFT, you 56 * may want to avoid using RNDIS on purely operational grounds. 57 * 58 * Omissions from the RNDIS 1.0 specification include: 59 * 60 * - Power management ... references data that's scattered around lots 61 * of other documentation, which is incorrect/incomplete there too. 62 * 63 * - There are various undocumented protocol requirements, like the need 64 * to send garbage in some control-OUT messages. 65 * 66 * - MS-Windows drivers sometimes emit undocumented requests. 67 */ 68 69struct f_rndis { 70 struct gether port; 71 u8 ctrl_id, data_id; 72 u8 ethaddr[ETH_ALEN]; 73 u32 vendorID; 74 const char *manufacturer; 75 struct rndis_params *params; 76 77 struct usb_ep *notify; 78 struct usb_request *notify_req; 79 atomic_t notify_count; 80}; 81 82static inline struct f_rndis *func_to_rndis(struct usb_function *f) 83{ 84 return container_of(f, struct f_rndis, port.func); 85} 86 87/* peak (theoretical) bulk transfer rate in bits-per-second */ 88static unsigned int bitrate(struct usb_gadget *g) 89{ 90 if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS) 91 return 4250000000U; 92 if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER) 93 return 3750000000U; 94 else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH) 95 return 13 * 512 * 8 * 1000 * 8; 96 else 97 return 19 * 64 * 1 * 1000 * 8; 98} 99 100/*-------------------------------------------------------------------------*/ 101 102/* 103 */ 104 105#define RNDIS_STATUS_INTERVAL_MS 32 106#define STATUS_BYTECOUNT 8 /* 8 bytes data */ 107 108 109/* interface descriptor: */ 110 111static struct usb_interface_descriptor rndis_control_intf = { 112 .bLength = sizeof rndis_control_intf, 113 .bDescriptorType = USB_DT_INTERFACE, 114 115 /* .bInterfaceNumber = DYNAMIC */ 116 /* status endpoint is optional; this could be patched later */ 117 .bNumEndpoints = 1, 118 .bInterfaceClass = USB_CLASS_COMM, 119 .bInterfaceSubClass = USB_CDC_SUBCLASS_ACM, 120 .bInterfaceProtocol = USB_CDC_ACM_PROTO_VENDOR, 121 /* .iInterface = DYNAMIC */ 122}; 123 124static struct usb_cdc_header_desc header_desc = { 125 .bLength = sizeof header_desc, 126 .bDescriptorType = USB_DT_CS_INTERFACE, 127 .bDescriptorSubType = USB_CDC_HEADER_TYPE, 128 129 .bcdCDC = cpu_to_le16(0x0110), 130}; 131 132static struct usb_cdc_call_mgmt_descriptor call_mgmt_descriptor = { 133 .bLength = sizeof call_mgmt_descriptor, 134 .bDescriptorType = USB_DT_CS_INTERFACE, 135 .bDescriptorSubType = USB_CDC_CALL_MANAGEMENT_TYPE, 136 137 .bmCapabilities = 0x00, 138 .bDataInterface = 0x01, 139}; 140 141static struct usb_cdc_acm_descriptor rndis_acm_descriptor = { 142 .bLength = sizeof rndis_acm_descriptor, 143 .bDescriptorType = USB_DT_CS_INTERFACE, 144 .bDescriptorSubType = USB_CDC_ACM_TYPE, 145 146 .bmCapabilities = 0x00, 147}; 148 149static struct usb_cdc_union_desc rndis_union_desc = { 150 .bLength = sizeof(rndis_union_desc), 151 .bDescriptorType = USB_DT_CS_INTERFACE, 152 .bDescriptorSubType = USB_CDC_UNION_TYPE, 153 /* .bMasterInterface0 = DYNAMIC */ 154 /* .bSlaveInterface0 = DYNAMIC */ 155}; 156 157/* the data interface has two bulk endpoints */ 158 159static struct usb_interface_descriptor rndis_data_intf = { 160 .bLength = sizeof rndis_data_intf, 161 .bDescriptorType = USB_DT_INTERFACE, 162 163 /* .bInterfaceNumber = DYNAMIC */ 164 .bNumEndpoints = 2, 165 .bInterfaceClass = USB_CLASS_CDC_DATA, 166 .bInterfaceSubClass = 0, 167 .bInterfaceProtocol = 0, 168 /* .iInterface = DYNAMIC */ 169}; 170 171 172static struct usb_interface_assoc_descriptor 173rndis_iad_descriptor = { 174 .bLength = sizeof rndis_iad_descriptor, 175 .bDescriptorType = USB_DT_INTERFACE_ASSOCIATION, 176 177 .bFirstInterface = 0, /* XXX, hardcoded */ 178 .bInterfaceCount = 2, // control + data 179 .bFunctionClass = USB_CLASS_COMM, 180 .bFunctionSubClass = USB_CDC_SUBCLASS_ETHERNET, 181 .bFunctionProtocol = USB_CDC_PROTO_NONE, 182 /* .iFunction = DYNAMIC */ 183}; 184 185/* full speed support: */ 186 187static struct usb_endpoint_descriptor fs_notify_desc = { 188 .bLength = USB_DT_ENDPOINT_SIZE, 189 .bDescriptorType = USB_DT_ENDPOINT, 190 191 .bEndpointAddress = USB_DIR_IN, 192 .bmAttributes = USB_ENDPOINT_XFER_INT, 193 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT), 194 .bInterval = RNDIS_STATUS_INTERVAL_MS, 195}; 196 197static struct usb_endpoint_descriptor fs_in_desc = { 198 .bLength = USB_DT_ENDPOINT_SIZE, 199 .bDescriptorType = USB_DT_ENDPOINT, 200 201 .bEndpointAddress = USB_DIR_IN, 202 .bmAttributes = USB_ENDPOINT_XFER_BULK, 203}; 204 205static struct usb_endpoint_descriptor fs_out_desc = { 206 .bLength = USB_DT_ENDPOINT_SIZE, 207 .bDescriptorType = USB_DT_ENDPOINT, 208 209 .bEndpointAddress = USB_DIR_OUT, 210 .bmAttributes = USB_ENDPOINT_XFER_BULK, 211}; 212 213static struct usb_descriptor_header *eth_fs_function[] = { 214 (struct usb_descriptor_header *) &rndis_iad_descriptor, 215 216 /* control interface matches ACM, not Ethernet */ 217 (struct usb_descriptor_header *) &rndis_control_intf, 218 (struct usb_descriptor_header *) &header_desc, 219 (struct usb_descriptor_header *) &call_mgmt_descriptor, 220 (struct usb_descriptor_header *) &rndis_acm_descriptor, 221 (struct usb_descriptor_header *) &rndis_union_desc, 222 (struct usb_descriptor_header *) &fs_notify_desc, 223 224 /* data interface has no altsetting */ 225 (struct usb_descriptor_header *) &rndis_data_intf, 226 (struct usb_descriptor_header *) &fs_in_desc, 227 (struct usb_descriptor_header *) &fs_out_desc, 228 NULL, 229}; 230 231/* high speed support: */ 232 233static struct usb_endpoint_descriptor hs_notify_desc = { 234 .bLength = USB_DT_ENDPOINT_SIZE, 235 .bDescriptorType = USB_DT_ENDPOINT, 236 237 .bEndpointAddress = USB_DIR_IN, 238 .bmAttributes = USB_ENDPOINT_XFER_INT, 239 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT), 240 .bInterval = USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS) 241}; 242 243static struct usb_endpoint_descriptor hs_in_desc = { 244 .bLength = USB_DT_ENDPOINT_SIZE, 245 .bDescriptorType = USB_DT_ENDPOINT, 246 247 .bEndpointAddress = USB_DIR_IN, 248 .bmAttributes = USB_ENDPOINT_XFER_BULK, 249 .wMaxPacketSize = cpu_to_le16(512), 250}; 251 252static struct usb_endpoint_descriptor hs_out_desc = { 253 .bLength = USB_DT_ENDPOINT_SIZE, 254 .bDescriptorType = USB_DT_ENDPOINT, 255 256 .bEndpointAddress = USB_DIR_OUT, 257 .bmAttributes = USB_ENDPOINT_XFER_BULK, 258 .wMaxPacketSize = cpu_to_le16(512), 259}; 260 261static struct usb_descriptor_header *eth_hs_function[] = { 262 (struct usb_descriptor_header *) &rndis_iad_descriptor, 263 264 /* control interface matches ACM, not Ethernet */ 265 (struct usb_descriptor_header *) &rndis_control_intf, 266 (struct usb_descriptor_header *) &header_desc, 267 (struct usb_descriptor_header *) &call_mgmt_descriptor, 268 (struct usb_descriptor_header *) &rndis_acm_descriptor, 269 (struct usb_descriptor_header *) &rndis_union_desc, 270 (struct usb_descriptor_header *) &hs_notify_desc, 271 272 /* data interface has no altsetting */ 273 (struct usb_descriptor_header *) &rndis_data_intf, 274 (struct usb_descriptor_header *) &hs_in_desc, 275 (struct usb_descriptor_header *) &hs_out_desc, 276 NULL, 277}; 278 279/* super speed support: */ 280 281static struct usb_endpoint_descriptor ss_notify_desc = { 282 .bLength = USB_DT_ENDPOINT_SIZE, 283 .bDescriptorType = USB_DT_ENDPOINT, 284 285 .bEndpointAddress = USB_DIR_IN, 286 .bmAttributes = USB_ENDPOINT_XFER_INT, 287 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT), 288 .bInterval = USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS) 289}; 290 291static struct usb_ss_ep_comp_descriptor ss_intr_comp_desc = { 292 .bLength = sizeof ss_intr_comp_desc, 293 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 294 295 /* the following 3 values can be tweaked if necessary */ 296 /* .bMaxBurst = 0, */ 297 /* .bmAttributes = 0, */ 298 .wBytesPerInterval = cpu_to_le16(STATUS_BYTECOUNT), 299}; 300 301static struct usb_endpoint_descriptor ss_in_desc = { 302 .bLength = USB_DT_ENDPOINT_SIZE, 303 .bDescriptorType = USB_DT_ENDPOINT, 304 305 .bEndpointAddress = USB_DIR_IN, 306 .bmAttributes = USB_ENDPOINT_XFER_BULK, 307 .wMaxPacketSize = cpu_to_le16(1024), 308}; 309 310static struct usb_endpoint_descriptor ss_out_desc = { 311 .bLength = USB_DT_ENDPOINT_SIZE, 312 .bDescriptorType = USB_DT_ENDPOINT, 313 314 .bEndpointAddress = USB_DIR_OUT, 315 .bmAttributes = USB_ENDPOINT_XFER_BULK, 316 .wMaxPacketSize = cpu_to_le16(1024), 317}; 318 319static struct usb_ss_ep_comp_descriptor ss_bulk_comp_desc = { 320 .bLength = sizeof ss_bulk_comp_desc, 321 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 322 323 /* the following 2 values can be tweaked if necessary */ 324 /* .bMaxBurst = 0, */ 325 /* .bmAttributes = 0, */ 326}; 327 328static struct usb_descriptor_header *eth_ss_function[] = { 329 (struct usb_descriptor_header *) &rndis_iad_descriptor, 330 331 /* control interface matches ACM, not Ethernet */ 332 (struct usb_descriptor_header *) &rndis_control_intf, 333 (struct usb_descriptor_header *) &header_desc, 334 (struct usb_descriptor_header *) &call_mgmt_descriptor, 335 (struct usb_descriptor_header *) &rndis_acm_descriptor, 336 (struct usb_descriptor_header *) &rndis_union_desc, 337 (struct usb_descriptor_header *) &ss_notify_desc, 338 (struct usb_descriptor_header *) &ss_intr_comp_desc, 339 340 /* data interface has no altsetting */ 341 (struct usb_descriptor_header *) &rndis_data_intf, 342 (struct usb_descriptor_header *) &ss_in_desc, 343 (struct usb_descriptor_header *) &ss_bulk_comp_desc, 344 (struct usb_descriptor_header *) &ss_out_desc, 345 (struct usb_descriptor_header *) &ss_bulk_comp_desc, 346 NULL, 347}; 348 349/* string descriptors: */ 350 351static struct usb_string rndis_string_defs[] = { 352 [0].s = "RNDIS Communications Control", 353 [1].s = "RNDIS Ethernet Data", 354 [2].s = "RNDIS", 355 { } /* end of list */ 356}; 357 358static struct usb_gadget_strings rndis_string_table = { 359 .language = 0x0409, /* en-us */ 360 .strings = rndis_string_defs, 361}; 362 363static struct usb_gadget_strings *rndis_strings[] = { 364 &rndis_string_table, 365 NULL, 366}; 367 368/*-------------------------------------------------------------------------*/ 369 370static struct sk_buff *rndis_add_header(struct gether *port, 371 struct sk_buff *skb) 372{ 373 struct sk_buff *skb2; 374 375 if (!skb) 376 return NULL; 377 378 skb2 = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type)); 379 rndis_add_hdr(skb2); 380 381 dev_kfree_skb(skb); 382 return skb2; 383} 384 385static void rndis_response_available(void *_rndis) 386{ 387 struct f_rndis *rndis = _rndis; 388 struct usb_request *req = rndis->notify_req; 389 struct usb_composite_dev *cdev = rndis->port.func.config->cdev; 390 __le32 *data = req->buf; 391 int status; 392 393 if (atomic_inc_return(&rndis->notify_count) != 1) 394 return; 395 396 /* Send RNDIS RESPONSE_AVAILABLE notification; a 397 * USB_CDC_NOTIFY_RESPONSE_AVAILABLE "should" work too 398 * 399 * This is the only notification defined by RNDIS. 400 */ 401 data[0] = cpu_to_le32(1); 402 data[1] = cpu_to_le32(0); 403 404 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC); 405 if (status) { 406 atomic_dec(&rndis->notify_count); 407 DBG(cdev, "notify/0 --> %d\n", status); 408 } 409} 410 411static void rndis_response_complete(struct usb_ep *ep, struct usb_request *req) 412{ 413 struct f_rndis *rndis = req->context; 414 struct usb_composite_dev *cdev = rndis->port.func.config->cdev; 415 int status = req->status; 416 417 /* after TX: 418 * - USB_CDC_GET_ENCAPSULATED_RESPONSE (ep0/control) 419 * - RNDIS_RESPONSE_AVAILABLE (status/irq) 420 */ 421 switch (status) { 422 case -ECONNRESET: 423 case -ESHUTDOWN: 424 /* connection gone */ 425 atomic_set(&rndis->notify_count, 0); 426 break; 427 default: 428 DBG(cdev, "RNDIS %s response error %d, %d/%d\n", 429 ep->name, status, 430 req->actual, req->length); 431 fallthrough; 432 case 0: 433 if (ep != rndis->notify) 434 break; 435 436 /* handle multiple pending RNDIS_RESPONSE_AVAILABLE 437 * notifications by resending until we're done 438 */ 439 if (atomic_dec_and_test(&rndis->notify_count)) 440 break; 441 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC); 442 if (status) { 443 atomic_dec(&rndis->notify_count); 444 DBG(cdev, "notify/1 --> %d\n", status); 445 } 446 break; 447 } 448} 449 450static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req) 451{ 452 struct f_rndis *rndis = req->context; 453 int status; 454 455 /* received RNDIS command from USB_CDC_SEND_ENCAPSULATED_COMMAND */ 456// spin_lock(&dev->lock); 457 status = rndis_msg_parser(rndis->params, (u8 *) req->buf); 458 if (status < 0) 459 pr_err("RNDIS command error %d, %d/%d\n", 460 status, req->actual, req->length); 461// spin_unlock(&dev->lock); 462} 463 464static int 465rndis_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) 466{ 467 struct f_rndis *rndis = func_to_rndis(f); 468 struct usb_composite_dev *cdev = f->config->cdev; 469 struct usb_request *req = cdev->req; 470 int value = -EOPNOTSUPP; 471 u16 w_index = le16_to_cpu(ctrl->wIndex); 472 u16 w_value = le16_to_cpu(ctrl->wValue); 473 u16 w_length = le16_to_cpu(ctrl->wLength); 474 475 /* composite driver infrastructure handles everything except 476 * CDC class messages; interface activation uses set_alt(). 477 */ 478 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) { 479 480 /* RNDIS uses the CDC command encapsulation mechanism to implement 481 * an RPC scheme, with much getting/setting of attributes by OID. 482 */ 483 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) 484 | USB_CDC_SEND_ENCAPSULATED_COMMAND: 485 if (w_value || w_index != rndis->ctrl_id) 486 goto invalid; 487 /* read the request; process it later */ 488 value = w_length; 489 req->complete = rndis_command_complete; 490 req->context = rndis; 491 /* later, rndis_response_available() sends a notification */ 492 break; 493 494 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) 495 | USB_CDC_GET_ENCAPSULATED_RESPONSE: 496 if (w_value || w_index != rndis->ctrl_id) 497 goto invalid; 498 else { 499 u8 *buf; 500 u32 n; 501 502 /* return the result */ 503 buf = rndis_get_next_response(rndis->params, &n); 504 if (buf) { 505 memcpy(req->buf, buf, n); 506 req->complete = rndis_response_complete; 507 req->context = rndis; 508 rndis_free_response(rndis->params, buf); 509 value = n; 510 } 511 /* else stalls ... spec says to avoid that */ 512 } 513 break; 514 515 default: 516invalid: 517 VDBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n", 518 ctrl->bRequestType, ctrl->bRequest, 519 w_value, w_index, w_length); 520 } 521 522 /* respond with data transfer or status phase? */ 523 if (value >= 0) { 524 DBG(cdev, "rndis req%02x.%02x v%04x i%04x l%d\n", 525 ctrl->bRequestType, ctrl->bRequest, 526 w_value, w_index, w_length); 527 req->zero = (value < w_length); 528 req->length = value; 529 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC); 530 if (value < 0) 531 ERROR(cdev, "rndis response on err %d\n", value); 532 } 533 534 /* device either stalls (value < 0) or reports success */ 535 return value; 536} 537 538 539static int rndis_set_alt(struct usb_function *f, unsigned intf, unsigned alt) 540{ 541 struct f_rndis *rndis = func_to_rndis(f); 542 struct usb_composite_dev *cdev = f->config->cdev; 543 544 /* we know alt == 0 */ 545 546 if (intf == rndis->ctrl_id) { 547 VDBG(cdev, "reset rndis control %d\n", intf); 548 usb_ep_disable(rndis->notify); 549 550 if (!rndis->notify->desc) { 551 VDBG(cdev, "init rndis ctrl %d\n", intf); 552 if (config_ep_by_speed(cdev->gadget, f, rndis->notify)) 553 goto fail; 554 } 555 usb_ep_enable(rndis->notify); 556 557 } else if (intf == rndis->data_id) { 558 struct net_device *net; 559 560 if (rndis->port.in_ep->enabled) { 561 DBG(cdev, "reset rndis\n"); 562 gether_disconnect(&rndis->port); 563 } 564 565 if (!rndis->port.in_ep->desc || !rndis->port.out_ep->desc) { 566 DBG(cdev, "init rndis\n"); 567 if (config_ep_by_speed(cdev->gadget, f, 568 rndis->port.in_ep) || 569 config_ep_by_speed(cdev->gadget, f, 570 rndis->port.out_ep)) { 571 rndis->port.in_ep->desc = NULL; 572 rndis->port.out_ep->desc = NULL; 573 goto fail; 574 } 575 } 576 577 /* Avoid ZLPs; they can be troublesome. */ 578 rndis->port.is_zlp_ok = false; 579 580 /* RNDIS should be in the "RNDIS uninitialized" state, 581 * either never activated or after rndis_uninit(). 582 * 583 * We don't want data to flow here until a nonzero packet 584 * filter is set, at which point it enters "RNDIS data 585 * initialized" state ... but we do want the endpoints 586 * to be activated. It's a strange little state. 587 * 588 * REVISIT the RNDIS gadget code has done this wrong for a 589 * very long time. We need another call to the link layer 590 * code -- gether_updown(...bool) maybe -- to do it right. 591 */ 592 rndis->port.cdc_filter = 0; 593 594 DBG(cdev, "RNDIS RX/TX early activation ... \n"); 595 net = gether_connect(&rndis->port); 596 if (IS_ERR(net)) 597 return PTR_ERR(net); 598 599 rndis_set_param_dev(rndis->params, net, 600 &rndis->port.cdc_filter); 601 } else 602 goto fail; 603 604 return 0; 605fail: 606 return -EINVAL; 607} 608 609static void rndis_disable(struct usb_function *f) 610{ 611 struct f_rndis *rndis = func_to_rndis(f); 612 struct usb_composite_dev *cdev = f->config->cdev; 613 614 if (!rndis->notify->enabled) 615 return; 616 617 DBG(cdev, "rndis deactivated\n"); 618 619 rndis_uninit(rndis->params); 620 gether_disconnect(&rndis->port); 621 622 usb_ep_disable(rndis->notify); 623 rndis->notify->desc = NULL; 624} 625 626/*-------------------------------------------------------------------------*/ 627 628/* 629 * This isn't quite the same mechanism as CDC Ethernet, since the 630 * notification scheme passes less data, but the same set of link 631 * states must be tested. A key difference is that altsettings are 632 * not used to tell whether the link should send packets or not. 633 */ 634 635static void rndis_open(struct gether *geth) 636{ 637 struct f_rndis *rndis = func_to_rndis(&geth->func); 638 struct usb_composite_dev *cdev = geth->func.config->cdev; 639 640 DBG(cdev, "%s\n", __func__); 641 642 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 643 bitrate(cdev->gadget) / 100); 644 rndis_signal_connect(rndis->params); 645} 646 647static void rndis_close(struct gether *geth) 648{ 649 struct f_rndis *rndis = func_to_rndis(&geth->func); 650 651 DBG(geth->func.config->cdev, "%s\n", __func__); 652 653 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 0); 654 rndis_signal_disconnect(rndis->params); 655} 656 657/*-------------------------------------------------------------------------*/ 658 659/* Some controllers can't support RNDIS ... */ 660static inline bool can_support_rndis(struct usb_configuration *c) 661{ 662 /* everything else is *presumably* fine */ 663 return true; 664} 665 666/* ethernet function driver setup/binding */ 667 668static int 669rndis_bind(struct usb_configuration *c, struct usb_function *f) 670{ 671 struct usb_composite_dev *cdev = c->cdev; 672 struct f_rndis *rndis = func_to_rndis(f); 673 struct usb_string *us; 674 int status; 675 struct usb_ep *ep; 676 677 struct f_rndis_opts *rndis_opts; 678 679 if (!can_support_rndis(c)) 680 return -EINVAL; 681 682 rndis_opts = container_of(f->fi, struct f_rndis_opts, func_inst); 683 684 if (cdev->use_os_string) { 685 f->os_desc_table = kzalloc(sizeof(*f->os_desc_table), 686 GFP_KERNEL); 687 if (!f->os_desc_table) 688 return -ENOMEM; 689 f->os_desc_n = 1; 690 f->os_desc_table[0].os_desc = &rndis_opts->rndis_os_desc; 691 } 692 693 rndis_iad_descriptor.bFunctionClass = rndis_opts->class; 694 rndis_iad_descriptor.bFunctionSubClass = rndis_opts->subclass; 695 rndis_iad_descriptor.bFunctionProtocol = rndis_opts->protocol; 696 697 /* 698 * in drivers/usb/gadget/configfs.c:configfs_composite_bind() 699 * configurations are bound in sequence with list_for_each_entry, 700 * in each configuration its functions are bound in sequence 701 * with list_for_each_entry, so we assume no race condition 702 * with regard to rndis_opts->bound access 703 */ 704 if (!rndis_opts->bound) { 705 gether_set_gadget(rndis_opts->net, cdev->gadget); 706 status = gether_register_netdev(rndis_opts->net); 707 if (status) 708 goto fail; 709 rndis_opts->bound = true; 710 } 711 712 us = usb_gstrings_attach(cdev, rndis_strings, 713 ARRAY_SIZE(rndis_string_defs)); 714 if (IS_ERR(us)) { 715 status = PTR_ERR(us); 716 goto fail; 717 } 718 rndis_control_intf.iInterface = us[0].id; 719 rndis_data_intf.iInterface = us[1].id; 720 rndis_iad_descriptor.iFunction = us[2].id; 721 722 /* allocate instance-specific interface IDs */ 723 status = usb_interface_id(c, f); 724 if (status < 0) 725 goto fail; 726 rndis->ctrl_id = status; 727 rndis_iad_descriptor.bFirstInterface = status; 728 729 rndis_control_intf.bInterfaceNumber = status; 730 rndis_union_desc.bMasterInterface0 = status; 731 732 if (cdev->use_os_string) 733 f->os_desc_table[0].if_id = 734 rndis_iad_descriptor.bFirstInterface; 735 736 status = usb_interface_id(c, f); 737 if (status < 0) 738 goto fail; 739 rndis->data_id = status; 740 741 rndis_data_intf.bInterfaceNumber = status; 742 rndis_union_desc.bSlaveInterface0 = status; 743 744 status = -ENODEV; 745 746 /* allocate instance-specific endpoints */ 747 ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc); 748 if (!ep) 749 goto fail; 750 rndis->port.in_ep = ep; 751 752 ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc); 753 if (!ep) 754 goto fail; 755 rndis->port.out_ep = ep; 756 757 /* NOTE: a status/notification endpoint is, strictly speaking, 758 * optional. We don't treat it that way though! It's simpler, 759 * and some newer profiles don't treat it as optional. 760 */ 761 ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc); 762 if (!ep) 763 goto fail; 764 rndis->notify = ep; 765 766 status = -ENOMEM; 767 768 /* allocate notification request and buffer */ 769 rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL); 770 if (!rndis->notify_req) 771 goto fail; 772 rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL); 773 if (!rndis->notify_req->buf) 774 goto fail; 775 rndis->notify_req->length = STATUS_BYTECOUNT; 776 rndis->notify_req->context = rndis; 777 rndis->notify_req->complete = rndis_response_complete; 778 779 /* support all relevant hardware speeds... we expect that when 780 * hardware is dual speed, all bulk-capable endpoints work at 781 * both speeds 782 */ 783 hs_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress; 784 hs_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress; 785 hs_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress; 786 787 ss_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress; 788 ss_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress; 789 ss_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress; 790 791 status = usb_assign_descriptors(f, eth_fs_function, eth_hs_function, 792 eth_ss_function, eth_ss_function); 793 if (status) 794 goto fail; 795 796 rndis->port.open = rndis_open; 797 rndis->port.close = rndis_close; 798 799 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 0); 800 rndis_set_host_mac(rndis->params, rndis->ethaddr); 801 802 if (rndis->manufacturer && rndis->vendorID && 803 rndis_set_param_vendor(rndis->params, rndis->vendorID, 804 rndis->manufacturer)) { 805 status = -EINVAL; 806 goto fail_free_descs; 807 } 808 809 /* NOTE: all that is done without knowing or caring about 810 * the network link ... which is unavailable to this code 811 * until we're activated via set_alt(). 812 */ 813 814 DBG(cdev, "RNDIS: %s speed IN/%s OUT/%s NOTIFY/%s\n", 815 gadget_is_superspeed(c->cdev->gadget) ? "super" : 816 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full", 817 rndis->port.in_ep->name, rndis->port.out_ep->name, 818 rndis->notify->name); 819 return 0; 820 821fail_free_descs: 822 usb_free_all_descriptors(f); 823fail: 824 kfree(f->os_desc_table); 825 f->os_desc_n = 0; 826 827 if (rndis->notify_req) { 828 kfree(rndis->notify_req->buf); 829 usb_ep_free_request(rndis->notify, rndis->notify_req); 830 } 831 832 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status); 833 834 return status; 835} 836 837void rndis_borrow_net(struct usb_function_instance *f, struct net_device *net) 838{ 839 struct f_rndis_opts *opts; 840 841 opts = container_of(f, struct f_rndis_opts, func_inst); 842 if (opts->bound) 843 gether_cleanup(netdev_priv(opts->net)); 844 else 845 free_netdev(opts->net); 846 opts->borrowed_net = opts->bound = true; 847 opts->net = net; 848} 849EXPORT_SYMBOL_GPL(rndis_borrow_net); 850 851static inline struct f_rndis_opts *to_f_rndis_opts(struct config_item *item) 852{ 853 return container_of(to_config_group(item), struct f_rndis_opts, 854 func_inst.group); 855} 856 857/* f_rndis_item_ops */ 858USB_ETHERNET_CONFIGFS_ITEM(rndis); 859 860/* f_rndis_opts_dev_addr */ 861USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(rndis); 862 863/* f_rndis_opts_host_addr */ 864USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(rndis); 865 866/* f_rndis_opts_qmult */ 867USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(rndis); 868 869/* f_rndis_opts_ifname */ 870USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(rndis); 871 872/* f_rndis_opts_class */ 873USB_ETHER_CONFIGFS_ITEM_ATTR_U8_RW(rndis, class); 874 875/* f_rndis_opts_subclass */ 876USB_ETHER_CONFIGFS_ITEM_ATTR_U8_RW(rndis, subclass); 877 878/* f_rndis_opts_protocol */ 879USB_ETHER_CONFIGFS_ITEM_ATTR_U8_RW(rndis, protocol); 880 881static struct configfs_attribute *rndis_attrs[] = { 882 &rndis_opts_attr_dev_addr, 883 &rndis_opts_attr_host_addr, 884 &rndis_opts_attr_qmult, 885 &rndis_opts_attr_ifname, 886 &rndis_opts_attr_class, 887 &rndis_opts_attr_subclass, 888 &rndis_opts_attr_protocol, 889 NULL, 890}; 891 892static const struct config_item_type rndis_func_type = { 893 .ct_item_ops = &rndis_item_ops, 894 .ct_attrs = rndis_attrs, 895 .ct_owner = THIS_MODULE, 896}; 897 898static void rndis_free_inst(struct usb_function_instance *f) 899{ 900 struct f_rndis_opts *opts; 901 902 opts = container_of(f, struct f_rndis_opts, func_inst); 903 if (!opts->borrowed_net) { 904 if (opts->bound) 905 gether_cleanup(netdev_priv(opts->net)); 906 else 907 free_netdev(opts->net); 908 } 909 910 kfree(opts->rndis_interf_group); /* single VLA chunk */ 911 kfree(opts); 912} 913 914static struct usb_function_instance *rndis_alloc_inst(void) 915{ 916 struct f_rndis_opts *opts; 917 struct usb_os_desc *descs[1]; 918 char *names[1]; 919 struct config_group *rndis_interf_group; 920 921 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 922 if (!opts) 923 return ERR_PTR(-ENOMEM); 924 opts->rndis_os_desc.ext_compat_id = opts->rndis_ext_compat_id; 925 926 mutex_init(&opts->lock); 927 opts->func_inst.free_func_inst = rndis_free_inst; 928 opts->net = gether_setup_default(); 929 if (IS_ERR(opts->net)) { 930 struct net_device *net = opts->net; 931 kfree(opts); 932 return ERR_CAST(net); 933 } 934 INIT_LIST_HEAD(&opts->rndis_os_desc.ext_prop); 935 936 opts->class = rndis_iad_descriptor.bFunctionClass; 937 opts->subclass = rndis_iad_descriptor.bFunctionSubClass; 938 opts->protocol = rndis_iad_descriptor.bFunctionProtocol; 939 940 descs[0] = &opts->rndis_os_desc; 941 names[0] = "rndis"; 942 config_group_init_type_name(&opts->func_inst.group, "", 943 &rndis_func_type); 944 rndis_interf_group = 945 usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs, 946 names, THIS_MODULE); 947 if (IS_ERR(rndis_interf_group)) { 948 rndis_free_inst(&opts->func_inst); 949 return ERR_CAST(rndis_interf_group); 950 } 951 opts->rndis_interf_group = rndis_interf_group; 952 953 return &opts->func_inst; 954} 955 956static void rndis_free(struct usb_function *f) 957{ 958 struct f_rndis *rndis; 959 struct f_rndis_opts *opts; 960 961 rndis = func_to_rndis(f); 962 rndis_deregister(rndis->params); 963 opts = container_of(f->fi, struct f_rndis_opts, func_inst); 964 kfree(rndis); 965 mutex_lock(&opts->lock); 966 opts->refcnt--; 967 mutex_unlock(&opts->lock); 968} 969 970static void rndis_unbind(struct usb_configuration *c, struct usb_function *f) 971{ 972 struct f_rndis *rndis = func_to_rndis(f); 973 974 kfree(f->os_desc_table); 975 f->os_desc_n = 0; 976 usb_free_all_descriptors(f); 977 978 kfree(rndis->notify_req->buf); 979 usb_ep_free_request(rndis->notify, rndis->notify_req); 980} 981 982static struct usb_function *rndis_alloc(struct usb_function_instance *fi) 983{ 984 struct f_rndis *rndis; 985 struct f_rndis_opts *opts; 986 struct rndis_params *params; 987 988 /* allocate and initialize one new instance */ 989 rndis = kzalloc(sizeof(*rndis), GFP_KERNEL); 990 if (!rndis) 991 return ERR_PTR(-ENOMEM); 992 993 opts = container_of(fi, struct f_rndis_opts, func_inst); 994 mutex_lock(&opts->lock); 995 opts->refcnt++; 996 997 gether_get_host_addr_u8(opts->net, rndis->ethaddr); 998 rndis->vendorID = opts->vendor_id; 999 rndis->manufacturer = opts->manufacturer; 1000 1001 rndis->port.ioport = netdev_priv(opts->net); 1002 mutex_unlock(&opts->lock); 1003 /* RNDIS activates when the host changes this filter */ 1004 rndis->port.cdc_filter = 0; 1005 1006 /* RNDIS has special (and complex) framing */ 1007 rndis->port.header_len = sizeof(struct rndis_packet_msg_type); 1008 rndis->port.wrap = rndis_add_header; 1009 rndis->port.unwrap = rndis_rm_hdr; 1010 1011 rndis->port.func.name = "rndis"; 1012 /* descriptors are per-instance copies */ 1013 rndis->port.func.bind = rndis_bind; 1014 rndis->port.func.unbind = rndis_unbind; 1015 rndis->port.func.set_alt = rndis_set_alt; 1016 rndis->port.func.setup = rndis_setup; 1017 rndis->port.func.disable = rndis_disable; 1018 rndis->port.func.free_func = rndis_free; 1019 1020 params = rndis_register(rndis_response_available, rndis); 1021 if (IS_ERR(params)) { 1022 kfree(rndis); 1023 return ERR_CAST(params); 1024 } 1025 rndis->params = params; 1026 1027 return &rndis->port.func; 1028} 1029 1030DECLARE_USB_FUNCTION_INIT(rndis, rndis_alloc_inst, rndis_alloc); 1031MODULE_LICENSE("GPL"); 1032MODULE_AUTHOR("David Brownell"); 1033