1 /* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #define TRACE_TAG USB 18 19 #include "sysdeps.h" 20 21 #include <ctype.h> 22 #include <dirent.h> 23 #include <errno.h> 24 #include <fcntl.h> 25 #include <linux/usb/ch9.h> 26 #include <linux/usbdevice_fs.h> 27 #include <linux/version.h> 28 #include <stdio.h> 29 #include <stdlib.h> 30 #include <string.h> 31 #include <sys/ioctl.h> 32 #include <sys/time.h> 33 #include <sys/types.h> 34 #include <unistd.h> 35 36 #include <chrono> 37 #include <condition_variable> 38 #include <list> 39 #include <mutex> 40 #include <string> 41 #include <thread> 42 43 #include <android-base/file.h> 44 #include <android-base/stringprintf.h> 45 #include <android-base/strings.h> 46 47 #include "adb.h" 48 #include "transport.h" 49 #include "usb.h" 50 51 using namespace std::chrono_literals; 52 using namespace std::literals; 53 54 /* usb scan debugging is waaaay too verbose */ 55 #define DBGX(x...) 56 57 namespace native { 58 struct usb_handle : public ::usb_handle { 59 ~usb_handle() { 60 if (fd != -1) unix_close(fd); 61 } 62 63 std::string path; 64 int fd = -1; 65 unsigned char ep_in; 66 unsigned char ep_out; 67 68 size_t max_packet_size; 69 unsigned zero_mask; 70 unsigned writeable = 1; 71 72 usbdevfs_urb urb_in; 73 usbdevfs_urb urb_out; 74 75 bool urb_in_busy = false; 76 bool urb_out_busy = false; 77 bool dead = false; 78 79 std::condition_variable cv; 80 std::mutex mutex; 81 82 // for garbage collecting disconnected devices 83 bool mark; 84 85 // ID of thread currently in REAPURB 86 pthread_t reaper_thread = 0; 87 }; 88 89 static auto& g_usb_handles_mutex = *new std::mutex(); 90 static auto& g_usb_handles = *new std::list<usb_handle*>(); 91 92 static int is_known_device(const char* dev_name) { 93 std::lock_guard<std::mutex> lock(g_usb_handles_mutex); 94 for (usb_handle* usb : g_usb_handles) { 95 if (usb->path == dev_name) { 96 // set mark flag to indicate this device is still alive 97 usb->mark = true; 98 return 1; 99 } 100 } 101 return 0; 102 } 103 104 static void kick_disconnected_devices() { 105 std::lock_guard<std::mutex> lock(g_usb_handles_mutex); 106 // kick any devices in the device list that were not found in the device scan 107 for (usb_handle* usb : g_usb_handles) { 108 if (!usb->mark) { 109 usb_kick(usb); 110 } else { 111 usb->mark = false; 112 } 113 } 114 } 115 116 static inline bool contains_non_digit(const char* name) { 117 while (*name) { 118 if (!isdigit(*name++)) return true; 119 } 120 return false; 121 } 122 123 static void find_usb_device(const std::string& base, 124 void (*register_device_callback)(const char*, const char*, 125 unsigned char, unsigned char, int, int, 126 unsigned, size_t)) { 127 std::unique_ptr<DIR, int(*)(DIR*)> bus_dir(opendir(base.c_str()), closedir); 128 if (!bus_dir) return; 129 130 dirent* de; 131 while ((de = readdir(bus_dir.get())) != 0) { 132 if (contains_non_digit(de->d_name)) continue; 133 134 std::string bus_name = base + "/" + de->d_name; 135 136 std::unique_ptr<DIR, int(*)(DIR*)> dev_dir(opendir(bus_name.c_str()), closedir); 137 if (!dev_dir) continue; 138 139 while ((de = readdir(dev_dir.get()))) { 140 unsigned char devdesc[4096]; 141 unsigned char* bufptr = devdesc; 142 unsigned char* bufend; 143 struct usb_device_descriptor* device; 144 struct usb_config_descriptor* config; 145 struct usb_interface_descriptor* interface; 146 struct usb_endpoint_descriptor *ep1, *ep2; 147 unsigned zero_mask = 0; 148 size_t max_packet_size = 0; 149 unsigned vid, pid; 150 151 if (contains_non_digit(de->d_name)) continue; 152 153 std::string dev_name = bus_name + "/" + de->d_name; 154 if (is_known_device(dev_name.c_str())) { 155 continue; 156 } 157 158 int fd = unix_open(dev_name.c_str(), O_RDONLY | O_CLOEXEC); 159 if (fd == -1) { 160 continue; 161 } 162 163 size_t desclength = unix_read(fd, devdesc, sizeof(devdesc)); 164 bufend = bufptr + desclength; 165 166 // should have device and configuration descriptors, and atleast two endpoints 167 if (desclength < USB_DT_DEVICE_SIZE + USB_DT_CONFIG_SIZE) { 168 D("desclength %zu is too small", desclength); 169 unix_close(fd); 170 continue; 171 } 172 173 device = (struct usb_device_descriptor*)bufptr; 174 bufptr += USB_DT_DEVICE_SIZE; 175 176 if((device->bLength != USB_DT_DEVICE_SIZE) || (device->bDescriptorType != USB_DT_DEVICE)) { 177 unix_close(fd); 178 continue; 179 } 180 181 vid = device->idVendor; 182 pid = device->idProduct; 183 DBGX("[ %s is V:%04x P:%04x ]\n", dev_name.c_str(), vid, pid); 184 185 // should have config descriptor next 186 config = (struct usb_config_descriptor *)bufptr; 187 bufptr += USB_DT_CONFIG_SIZE; 188 if (config->bLength != USB_DT_CONFIG_SIZE || config->bDescriptorType != USB_DT_CONFIG) { 189 D("usb_config_descriptor not found"); 190 unix_close(fd); 191 continue; 192 } 193 194 // loop through all the descriptors and look for the ADB interface 195 while (bufptr < bufend) { 196 unsigned char length = bufptr[0]; 197 unsigned char type = bufptr[1]; 198 199 if (type == USB_DT_INTERFACE) { 200 interface = (struct usb_interface_descriptor *)bufptr; 201 bufptr += length; 202 203 if (length != USB_DT_INTERFACE_SIZE) { 204 D("interface descriptor has wrong size"); 205 break; 206 } 207 208 DBGX("bInterfaceClass: %d, bInterfaceSubClass: %d," 209 "bInterfaceProtocol: %d, bNumEndpoints: %d\n", 210 interface->bInterfaceClass, interface->bInterfaceSubClass, 211 interface->bInterfaceProtocol, interface->bNumEndpoints); 212 213 if (interface->bNumEndpoints == 2 && 214 is_adb_interface(interface->bInterfaceClass, interface->bInterfaceSubClass, 215 interface->bInterfaceProtocol)) { 216 struct stat st; 217 char pathbuf[128]; 218 char link[256]; 219 char *devpath = nullptr; 220 221 DBGX("looking for bulk endpoints\n"); 222 // looks like ADB... 223 ep1 = (struct usb_endpoint_descriptor *)bufptr; 224 bufptr += USB_DT_ENDPOINT_SIZE; 225 // For USB 3.0 SuperSpeed devices, skip potential 226 // USB 3.0 SuperSpeed Endpoint Companion descriptor 227 if (bufptr+2 <= devdesc + desclength && 228 bufptr[0] == USB_DT_SS_EP_COMP_SIZE && 229 bufptr[1] == USB_DT_SS_ENDPOINT_COMP) { 230 bufptr += USB_DT_SS_EP_COMP_SIZE; 231 } 232 ep2 = (struct usb_endpoint_descriptor *)bufptr; 233 bufptr += USB_DT_ENDPOINT_SIZE; 234 if (bufptr+2 <= devdesc + desclength && 235 bufptr[0] == USB_DT_SS_EP_COMP_SIZE && 236 bufptr[1] == USB_DT_SS_ENDPOINT_COMP) { 237 bufptr += USB_DT_SS_EP_COMP_SIZE; 238 } 239 240 if (bufptr > devdesc + desclength || 241 ep1->bLength != USB_DT_ENDPOINT_SIZE || 242 ep1->bDescriptorType != USB_DT_ENDPOINT || 243 ep2->bLength != USB_DT_ENDPOINT_SIZE || 244 ep2->bDescriptorType != USB_DT_ENDPOINT) { 245 D("endpoints not found"); 246 break; 247 } 248 249 // both endpoints should be bulk 250 if (ep1->bmAttributes != USB_ENDPOINT_XFER_BULK || 251 ep2->bmAttributes != USB_ENDPOINT_XFER_BULK) { 252 D("bulk endpoints not found"); 253 continue; 254 } 255 /* aproto 01 needs 0 termination */ 256 if (interface->bInterfaceProtocol == ADB_PROTOCOL) { 257 max_packet_size = ep1->wMaxPacketSize; 258 zero_mask = ep1->wMaxPacketSize - 1; 259 } 260 261 // we have a match. now we just need to figure out which is in and which is out. 262 unsigned char local_ep_in, local_ep_out; 263 if (ep1->bEndpointAddress & USB_ENDPOINT_DIR_MASK) { 264 local_ep_in = ep1->bEndpointAddress; 265 local_ep_out = ep2->bEndpointAddress; 266 } else { 267 local_ep_in = ep2->bEndpointAddress; 268 local_ep_out = ep1->bEndpointAddress; 269 } 270 271 // Determine the device path 272 if (!fstat(fd, &st) && S_ISCHR(st.st_mode)) { 273 snprintf(pathbuf, sizeof(pathbuf), "/sys/dev/char/%d:%d", 274 major(st.st_rdev), minor(st.st_rdev)); 275 ssize_t link_len = readlink(pathbuf, link, sizeof(link) - 1); 276 if (link_len > 0) { 277 link[link_len] = '\0'; 278 const char* slash = strrchr(link, '/'); 279 if (slash) { 280 snprintf(pathbuf, sizeof(pathbuf), 281 "usb:%s", slash + 1); 282 devpath = pathbuf; 283 } 284 } 285 } 286 287 register_device_callback(dev_name.c_str(), devpath, local_ep_in, 288 local_ep_out, interface->bInterfaceNumber, 289 device->iSerialNumber, zero_mask, max_packet_size); 290 break; 291 } 292 } else { 293 bufptr += length; 294 } 295 } // end of while 296 297 unix_close(fd); 298 } 299 } 300 } 301 302 static int usb_bulk_write(usb_handle* h, const void* data, int len) { 303 std::unique_lock<std::mutex> lock(h->mutex); 304 D("++ usb_bulk_write ++"); 305 306 usbdevfs_urb* urb = &h->urb_out; 307 memset(urb, 0, sizeof(*urb)); 308 urb->type = USBDEVFS_URB_TYPE_BULK; 309 urb->endpoint = h->ep_out; 310 urb->status = -1; 311 urb->buffer = const_cast<void*>(data); 312 urb->buffer_length = len; 313 314 if (h->dead) { 315 errno = EINVAL; 316 return -1; 317 } 318 319 if (TEMP_FAILURE_RETRY(ioctl(h->fd, USBDEVFS_SUBMITURB, urb)) == -1) { 320 return -1; 321 } 322 323 h->urb_out_busy = true; 324 while (true) { 325 auto now = std::chrono::system_clock::now(); 326 if (h->cv.wait_until(lock, now + 5s) == std::cv_status::timeout || h->dead) { 327 // TODO: call USBDEVFS_DISCARDURB? 328 errno = ETIMEDOUT; 329 return -1; 330 } 331 if (!h->urb_out_busy) { 332 if (urb->status != 0) { 333 errno = -urb->status; 334 return -1; 335 } 336 return urb->actual_length; 337 } 338 } 339 } 340 341 static int usb_bulk_read(usb_handle* h, void* data, int len) { 342 std::unique_lock<std::mutex> lock(h->mutex); 343 D("++ usb_bulk_read ++"); 344 345 usbdevfs_urb* urb = &h->urb_in; 346 memset(urb, 0, sizeof(*urb)); 347 urb->type = USBDEVFS_URB_TYPE_BULK; 348 urb->endpoint = h->ep_in; 349 urb->status = -1; 350 urb->buffer = data; 351 urb->buffer_length = len; 352 353 if (h->dead) { 354 errno = EINVAL; 355 return -1; 356 } 357 358 if (TEMP_FAILURE_RETRY(ioctl(h->fd, USBDEVFS_SUBMITURB, urb)) == -1) { 359 return -1; 360 } 361 362 h->urb_in_busy = true; 363 while (true) { 364 D("[ reap urb - wait ]"); 365 h->reaper_thread = pthread_self(); 366 int fd = h->fd; 367 lock.unlock(); 368 369 // This ioctl must not have TEMP_FAILURE_RETRY because we send SIGALRM to break out. 370 usbdevfs_urb* out = nullptr; 371 int res = ioctl(fd, USBDEVFS_REAPURB, &out); 372 int saved_errno = errno; 373 374 lock.lock(); 375 h->reaper_thread = 0; 376 if (h->dead) { 377 errno = EINVAL; 378 return -1; 379 } 380 if (res < 0) { 381 if (saved_errno == EINTR) { 382 continue; 383 } 384 D("[ reap urb - error ]"); 385 errno = saved_errno; 386 return -1; 387 } 388 D("[ urb @%p status = %d, actual = %d ]", out, out->status, out->actual_length); 389 390 if (out == &h->urb_in) { 391 D("[ reap urb - IN complete ]"); 392 h->urb_in_busy = false; 393 if (urb->status != 0) { 394 errno = -urb->status; 395 return -1; 396 } 397 return urb->actual_length; 398 } 399 if (out == &h->urb_out) { 400 D("[ reap urb - OUT compelete ]"); 401 h->urb_out_busy = false; 402 h->cv.notify_all(); 403 } 404 } 405 } 406 407 int usb_write(usb_handle *h, const void *_data, int len) 408 { 409 D("++ usb_write ++"); 410 411 unsigned char *data = (unsigned char*) _data; 412 int n = usb_bulk_write(h, data, len); 413 if (n != len) { 414 D("ERROR: n = %d, errno = %d (%s)", n, errno, strerror(errno)); 415 return -1; 416 } 417 418 if (h->zero_mask && !(len & h->zero_mask)) { 419 // If we need 0-markers and our transfer is an even multiple of the packet size, 420 // then send a zero marker. 421 return usb_bulk_write(h, _data, 0); 422 } 423 424 D("-- usb_write --"); 425 return 0; 426 } 427 428 int usb_read(usb_handle *h, void *_data, int len) 429 { 430 unsigned char *data = (unsigned char*) _data; 431 int n; 432 433 D("++ usb_read ++"); 434 int orig_len = len; 435 while (len == orig_len) { 436 int xfer = len; 437 438 D("[ usb read %d fd = %d], path=%s", xfer, h->fd, h->path.c_str()); 439 n = usb_bulk_read(h, data, xfer); 440 D("[ usb read %d ] = %d, path=%s", xfer, n, h->path.c_str()); 441 if (n <= 0) { 442 if((errno == ETIMEDOUT) && (h->fd != -1)) { 443 D("[ timeout ]"); 444 continue; 445 } 446 D("ERROR: n = %d, errno = %d (%s)", 447 n, errno, strerror(errno)); 448 return -1; 449 } 450 451 len -= n; 452 data += n; 453 } 454 455 D("-- usb_read --"); 456 return orig_len - len; 457 } 458 459 void usb_kick(usb_handle* h) { 460 std::lock_guard<std::mutex> lock(h->mutex); 461 D("[ kicking %p (fd = %d) ]", h, h->fd); 462 if (!h->dead) { 463 h->dead = true; 464 465 if (h->writeable) { 466 /* HACK ALERT! 467 ** Sometimes we get stuck in ioctl(USBDEVFS_REAPURB). 468 ** This is a workaround for that problem. 469 */ 470 if (h->reaper_thread) { 471 pthread_kill(h->reaper_thread, SIGALRM); 472 } 473 474 /* cancel any pending transactions 475 ** these will quietly fail if the txns are not active, 476 ** but this ensures that a reader blocked on REAPURB 477 ** will get unblocked 478 */ 479 ioctl(h->fd, USBDEVFS_DISCARDURB, &h->urb_in); 480 ioctl(h->fd, USBDEVFS_DISCARDURB, &h->urb_out); 481 h->urb_in.status = -ENODEV; 482 h->urb_out.status = -ENODEV; 483 h->urb_in_busy = false; 484 h->urb_out_busy = false; 485 h->cv.notify_all(); 486 } else { 487 unregister_usb_transport(h); 488 } 489 } 490 } 491 492 int usb_close(usb_handle* h) { 493 std::lock_guard<std::mutex> lock(g_usb_handles_mutex); 494 g_usb_handles.remove(h); 495 496 D("-- usb close %p (fd = %d) --", h, h->fd); 497 498 delete h; 499 500 return 0; 501 } 502 503 size_t usb_get_max_packet_size(usb_handle* h) { 504 return h->max_packet_size; 505 } 506 507 static void register_device(const char* dev_name, const char* dev_path, unsigned char ep_in, 508 unsigned char ep_out, int interface, int serial_index, 509 unsigned zero_mask, size_t max_packet_size) { 510 // Since Linux will not reassign the device ID (and dev_name) as long as the 511 // device is open, we can add to the list here once we open it and remove 512 // from the list when we're finally closed and everything will work out 513 // fine. 514 // 515 // If we have a usb_handle on the list of handles with a matching name, we 516 // have no further work to do. 517 { 518 std::lock_guard<std::mutex> lock(g_usb_handles_mutex); 519 for (usb_handle* usb: g_usb_handles) { 520 if (usb->path == dev_name) { 521 return; 522 } 523 } 524 } 525 526 D("[ usb located new device %s (%d/%d/%d) ]", dev_name, ep_in, ep_out, interface); 527 std::unique_ptr<usb_handle> usb(new usb_handle); 528 usb->path = dev_name; 529 usb->ep_in = ep_in; 530 usb->ep_out = ep_out; 531 usb->zero_mask = zero_mask; 532 usb->max_packet_size = max_packet_size; 533 534 // Initialize mark so we don't get garbage collected after the device scan. 535 usb->mark = true; 536 537 usb->fd = unix_open(usb->path.c_str(), O_RDWR | O_CLOEXEC); 538 if (usb->fd == -1) { 539 // Opening RW failed, so see if we have RO access. 540 usb->fd = unix_open(usb->path.c_str(), O_RDONLY | O_CLOEXEC); 541 if (usb->fd == -1) { 542 D("[ usb open %s failed: %s]", usb->path.c_str(), strerror(errno)); 543 return; 544 } 545 usb->writeable = 0; 546 } 547 548 D("[ usb opened %s%s, fd=%d]", 549 usb->path.c_str(), (usb->writeable ? "" : " (read-only)"), usb->fd); 550 551 if (usb->writeable) { 552 if (ioctl(usb->fd, USBDEVFS_CLAIMINTERFACE, &interface) != 0) { 553 D("[ usb ioctl(%d, USBDEVFS_CLAIMINTERFACE) failed: %s]", usb->fd, strerror(errno)); 554 return; 555 } 556 } 557 558 // Read the device's serial number. 559 std::string serial_path = android::base::StringPrintf( 560 "/sys/bus/usb/devices/%s/serial", dev_path + 4); 561 std::string serial; 562 if (!android::base::ReadFileToString(serial_path, &serial)) { 563 D("[ usb read %s failed: %s ]", serial_path.c_str(), strerror(errno)); 564 // We don't actually want to treat an unknown serial as an error because 565 // devices aren't able to communicate a serial number in early bringup. 566 // http://b/20883914 567 serial = ""; 568 } 569 serial = android::base::Trim(serial); 570 571 // Add to the end of the active handles. 572 usb_handle* done_usb = usb.release(); 573 { 574 std::lock_guard<std::mutex> lock(g_usb_handles_mutex); 575 g_usb_handles.push_back(done_usb); 576 } 577 register_usb_transport(done_usb, serial.c_str(), dev_path, done_usb->writeable); 578 } 579 580 static void device_poll_thread() { 581 adb_thread_setname("device poll"); 582 D("Created device thread"); 583 while (true) { 584 // TODO: Use inotify. 585 find_usb_device("/dev/bus/usb", register_device); 586 kick_disconnected_devices(); 587 std::this_thread::sleep_for(1s); 588 } 589 } 590 591 void usb_init() { 592 struct sigaction actions; 593 memset(&actions, 0, sizeof(actions)); 594 sigemptyset(&actions.sa_mask); 595 actions.sa_flags = 0; 596 actions.sa_handler = [](int) {}; 597 sigaction(SIGALRM, &actions, nullptr); 598 599 std::thread(device_poll_thread).detach(); 600 } 601 602 void usb_cleanup() {} 603 604 } // namespace native 605