hw/usb/dev-mtp.c

   1 /*
   2  * Media Transfer Protocol implementation, backed by host filesystem.
   3  *
   4  * Copyright Red Hat, Inc 2014
   5  *
   6  * Author:
   7  *   Gerd Hoffmann <[email protected]>
   8  *
   9  * This code is licensed under the GPL v2 or later.
  10  */
  11
  12 #include "qemu/osdep.h"
  13 #include "qapi/error.h"
  14 #include "qemu/error-report.h"
  15 #include <wchar.h>
  16 #include <dirent.h>
  17
  18 #include <sys/statvfs.h>
  19
  20
  21 #include "qemu/iov.h"
  22 #include "qemu/module.h"
  23 #include "qemu/filemonitor.h"
  24 #include "trace.h"
  25 #include "hw/usb.h"
  26 #include "desc.h"
  27 #include "qemu/units.h"
  28
  29 /* ----------------------------------------------------------------------- */
  30
  31 enum mtp_container_type {
  32     TYPE_COMMAND  = 1,
  33     TYPE_DATA     = 2,
  34     TYPE_RESPONSE = 3,
  35     TYPE_EVENT    = 4,
  36 };
  37
  38 /* MTP write stage, for internal use only */
  39 enum mtp_write_status {
  40     WRITE_START    = 1,
  41     WRITE_CONTINUE = 2,
  42     WRITE_END      = 3,
  43 };
  44
  45 enum mtp_code {
  46     /* command codes */
  47     CMD_GET_DEVICE_INFO            = 0x1001,
  48     CMD_OPEN_SESSION               = 0x1002,
  49     CMD_CLOSE_SESSION              = 0x1003,
  50     CMD_GET_STORAGE_IDS            = 0x1004,
  51     CMD_GET_STORAGE_INFO           = 0x1005,
  52     CMD_GET_NUM_OBJECTS            = 0x1006,
  53     CMD_GET_OBJECT_HANDLES         = 0x1007,
  54     CMD_GET_OBJECT_INFO            = 0x1008,
  55     CMD_GET_OBJECT                 = 0x1009,
  56     CMD_DELETE_OBJECT              = 0x100b,
  57     CMD_SEND_OBJECT_INFO           = 0x100c,
  58     CMD_SEND_OBJECT                = 0x100d,
  59     CMD_GET_PARTIAL_OBJECT         = 0x101b,
  60     CMD_GET_OBJECT_PROPS_SUPPORTED = 0x9801,
  61     CMD_GET_OBJECT_PROP_DESC       = 0x9802,
  62     CMD_GET_OBJECT_PROP_VALUE      = 0x9803,
  63
  64     /* response codes */
  65     RES_OK                         = 0x2001,
  66     RES_GENERAL_ERROR              = 0x2002,
  67     RES_SESSION_NOT_OPEN           = 0x2003,
  68     RES_INVALID_TRANSACTION_ID     = 0x2004,
  69     RES_OPERATION_NOT_SUPPORTED    = 0x2005,
  70     RES_PARAMETER_NOT_SUPPORTED    = 0x2006,
  71     RES_INCOMPLETE_TRANSFER        = 0x2007,
  72     RES_INVALID_STORAGE_ID         = 0x2008,
  73     RES_INVALID_OBJECT_HANDLE      = 0x2009,
  74     RES_INVALID_OBJECT_FORMAT_CODE = 0x200b,
  75     RES_STORE_FULL                 = 0x200c,
  76     RES_STORE_READ_ONLY            = 0x200e,
  77     RES_PARTIAL_DELETE             = 0x2012,
  78     RES_STORE_NOT_AVAILABLE        = 0x2013,
  79     RES_SPEC_BY_FORMAT_UNSUPPORTED = 0x2014,
  80     RES_INVALID_OBJECTINFO         = 0x2015,
  81     RES_DESTINATION_UNSUPPORTED    = 0x2020,
  82     RES_INVALID_PARENT_OBJECT      = 0x201a,
  83     RES_INVALID_PARAMETER          = 0x201d,
  84     RES_SESSION_ALREADY_OPEN       = 0x201e,
  85     RES_INVALID_OBJECT_PROP_CODE   = 0xA801,
  86
  87     /* format codes */
  88     FMT_UNDEFINED_OBJECT           = 0x3000,
  89     FMT_ASSOCIATION                = 0x3001,
  90
  91     /* event codes */
  92     EVT_CANCEL_TRANSACTION         = 0x4001,
  93     EVT_OBJ_ADDED                  = 0x4002,
  94     EVT_OBJ_REMOVED                = 0x4003,
  95     EVT_OBJ_INFO_CHANGED           = 0x4007,
  96
  97     /* object properties */
  98     PROP_STORAGE_ID                = 0xDC01,
  99     PROP_OBJECT_FORMAT             = 0xDC02,
 100     PROP_OBJECT_COMPRESSED_SIZE    = 0xDC04,
 101     PROP_PARENT_OBJECT             = 0xDC0B,
 102     PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER = 0xDC41,
 103     PROP_NAME                      = 0xDC44,
 104 };
 105
 106 enum mtp_data_type {
 107     DATA_TYPE_UINT16  = 0x0004,
 108     DATA_TYPE_UINT32  = 0x0006,
 109     DATA_TYPE_UINT64  = 0x0008,
 110     DATA_TYPE_UINT128 = 0x000a,
 111     DATA_TYPE_STRING  = 0xffff,
 112 };
 113
 114 typedef struct {
 115     uint32_t length;
 116     uint16_t type;
 117     uint16_t code;
 118     uint32_t trans;
 119 } QEMU_PACKED mtp_container;
 120
 121 /* ----------------------------------------------------------------------- */
 122
 123 typedef struct MTPState MTPState;
 124 typedef struct MTPControl MTPControl;
 125 typedef struct MTPData MTPData;
 126 typedef struct MTPObject MTPObject;
 127
 128 enum {
 129     EP_DATA_IN = 1,
 130     EP_DATA_OUT,
 131     EP_EVENT,
 132 };
 133
 134 typedef struct MTPMonEntry MTPMonEntry;
 135
 136 struct MTPMonEntry {
 137     uint32_t event;
 138     uint32_t handle;
 139
 140     QTAILQ_ENTRY(MTPMonEntry) next;
 141 };
 142
 143 struct MTPControl {
 144     uint16_t     code;
 145     uint32_t     trans;
 146     int          argc;
 147     uint32_t     argv[5];
 148 };
 149
 150 struct MTPData {
 151     uint16_t     code;
 152     uint32_t     trans;
 153     uint64_t     offset;
 154     uint64_t     length;
 155     uint64_t     alloc;
 156     uint8_t      *data;
 157     bool         first;
 158     /* Used for >4G file sizes */
 159     bool         pending;
 160     int          fd;
 161     uint8_t      write_status;
 162     /* Internal pointer per every MTP_WRITE_BUF_SZ */
 163     uint64_t     data_offset;
 164 };
 165
 166 struct MTPObject {
 167     uint32_t     handle;
 168     uint16_t     format;
 169     char         *name;
 170     char         *path;
 171     struct stat  stat;
 172     /* file monitor watch id */
 173     int64_t      watchid;
 174     MTPObject    *parent;
 175     uint32_t     nchildren;
 176     QLIST_HEAD(, MTPObject) children;
 177     QLIST_ENTRY(MTPObject) list;
 178     bool         have_children;
 179     QTAILQ_ENTRY(MTPObject) next;
 180 };
 181
 182 struct MTPState {
 183     USBDevice    dev;
 184     char         *root;
 185     char         *desc;
 186     uint32_t     flags;
 187
 188     MTPData      *data_in;
 189     MTPData      *data_out;
 190     MTPControl   *result;
 191     uint32_t     session;
 192     uint32_t     next_handle;
 193     bool         readonly;
 194
 195     QTAILQ_HEAD(, MTPObject) objects;
 196     QFileMonitor *file_monitor;
 197     QTAILQ_HEAD(, MTPMonEntry) events;
 198     /* Responder is expecting a write operation */
 199     bool write_pending;
 200     struct {
 201         uint32_t parent_handle;
 202         uint16_t format;
 203         uint32_t size;
 204         char *filename;
 205     } dataset;
 206 };
 207
 208 /*
 209  * ObjectInfo dataset received from initiator
 210  * Fields we don't care about are ignored
 211  */
 212 typedef struct {
 213     uint32_t storage_id; /*unused*/
 214     uint16_t format;
 215     uint16_t protection_status; /*unused*/
 216     uint32_t size;
 217     uint16_t thumb_format; /*unused*/
 218     uint32_t thumb_comp_sz; /*unused*/
 219     uint32_t thumb_pix_width; /*unused*/
 220     uint32_t thumb_pix_height; /*unused*/
 221     uint32_t image_pix_width; /*unused*/
 222     uint32_t image_pix_height; /*unused*/
 223     uint32_t image_bit_depth; /*unused*/
 224     uint32_t parent; /*unused*/
 225     uint16_t assoc_type;
 226     uint32_t assoc_desc;
 227     uint32_t seq_no; /*unused*/
 228     uint8_t length; /*part of filename field*/
 229     uint8_t filename[0]; /* UTF-16 encoded */
 230     char date_created[0]; /*unused*/
 231     char date_modified[0]; /*unused*/
 232     char keywords[0]; /*unused*/
 233     /* string and other data follows */
 234 } QEMU_PACKED ObjectInfo;
 235
 236 #define TYPE_USB_MTP "usb-mtp"
 237 #define USB_MTP(obj) OBJECT_CHECK(MTPState, (obj), TYPE_USB_MTP)
 238
 239 #define QEMU_STORAGE_ID 0x00010001
 240
 241 #define MTP_FLAG_WRITABLE 0
 242
 243 #define FLAG_SET(_mtp, _flag)  ((_mtp)->flags & (1 << (_flag)))
 244
 245 /* ----------------------------------------------------------------------- */
 246
 247 #define MTP_MANUFACTURER  "QEMU"
 248 #define MTP_PRODUCT       "QEMU filesharing"
 249 #define MTP_WRITE_BUF_SZ  (512 * KiB)
 250
 251 enum {
 252     STR_MANUFACTURER = 1,
 253     STR_PRODUCT,
 254     STR_SERIALNUMBER,
 255     STR_MTP,
 256     STR_CONFIG_FULL,
 257     STR_CONFIG_HIGH,
 258     STR_CONFIG_SUPER,
 259 };
 260
 261 static const USBDescStrings desc_strings = {
 262     [STR_MANUFACTURER] = MTP_MANUFACTURER,
 263     [STR_PRODUCT]      = MTP_PRODUCT,
 264     [STR_SERIALNUMBER] = "34617",
 265     [STR_MTP]          = "MTP",
 266     [STR_CONFIG_FULL]  = "Full speed config (usb 1.1)",
 267     [STR_CONFIG_HIGH]  = "High speed config (usb 2.0)",
 268     [STR_CONFIG_SUPER] = "Super speed config (usb 3.0)",
 269 };
 270
 271 static const USBDescIface desc_iface_full = {
 272     .bInterfaceNumber              = 0,
 273     .bNumEndpoints                 = 3,
 274     .bInterfaceClass               = USB_CLASS_STILL_IMAGE,
 275     .bInterfaceSubClass            = 0x01,
 276     .bInterfaceProtocol            = 0x01,
 277     .iInterface                    = STR_MTP,
 278     .eps = (USBDescEndpoint[]) {
 279         {
 280             .bEndpointAddress      = USB_DIR_IN | EP_DATA_IN,
 281             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
 282             .wMaxPacketSize        = 64,
 283         },{
 284             .bEndpointAddress      = USB_DIR_OUT | EP_DATA_OUT,
 285             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
 286             .wMaxPacketSize        = 64,
 287         },{
 288             .bEndpointAddress      = USB_DIR_IN | EP_EVENT,
 289             .bmAttributes          = USB_ENDPOINT_XFER_INT,
 290             .wMaxPacketSize        = 64,
 291             .bInterval             = 0x0a,
 292         },
 293     }
 294 };
 295
 296 static const USBDescDevice desc_device_full = {
 297     .bcdUSB                        = 0x0200,
 298     .bMaxPacketSize0               = 8,
 299     .bNumConfigurations            = 1,
 300     .confs = (USBDescConfig[]) {
 301         {
 302             .bNumInterfaces        = 1,
 303             .bConfigurationValue   = 1,
 304             .iConfiguration        = STR_CONFIG_FULL,
 305             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_WAKEUP,
 306             .bMaxPower             = 2,
 307             .nif = 1,
 308             .ifs = &desc_iface_full,
 309         },
 310     },
 311 };
 312
 313 static const USBDescIface desc_iface_high = {
 314     .bInterfaceNumber              = 0,
 315     .bNumEndpoints                 = 3,
 316     .bInterfaceClass               = USB_CLASS_STILL_IMAGE,
 317     .bInterfaceSubClass            = 0x01,
 318     .bInterfaceProtocol            = 0x01,
 319     .iInterface                    = STR_MTP,
 320     .eps = (USBDescEndpoint[]) {
 321         {
 322             .bEndpointAddress      = USB_DIR_IN | EP_DATA_IN,
 323             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
 324             .wMaxPacketSize        = 512,
 325         },{
 326             .bEndpointAddress      = USB_DIR_OUT | EP_DATA_OUT,
 327             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
 328             .wMaxPacketSize        = 512,
 329         },{
 330             .bEndpointAddress      = USB_DIR_IN | EP_EVENT,
 331             .bmAttributes          = USB_ENDPOINT_XFER_INT,
 332             .wMaxPacketSize        = 64,
 333             .bInterval             = 0x0a,
 334         },
 335     }
 336 };
 337
 338 static const USBDescDevice desc_device_high = {
 339     .bcdUSB                        = 0x0200,
 340     .bMaxPacketSize0               = 64,
 341     .bNumConfigurations            = 1,
 342     .confs = (USBDescConfig[]) {
 343         {
 344             .bNumInterfaces        = 1,
 345             .bConfigurationValue   = 1,
 346             .iConfiguration        = STR_CONFIG_HIGH,
 347             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_WAKEUP,
 348             .bMaxPower             = 2,
 349             .nif = 1,
 350             .ifs = &desc_iface_high,
 351         },
 352     },
 353 };
 354
 355 static const USBDescMSOS desc_msos = {
 356     .CompatibleID = "MTP",
 357     .SelectiveSuspendEnabled = true,
 358 };
 359
 360 static const USBDesc desc = {
 361     .id = {
 362         .idVendor          = 0x46f4, /* CRC16() of "QEMU" */
 363         .idProduct         = 0x0004,
 364         .bcdDevice         = 0,
 365         .iManufacturer     = STR_MANUFACTURER,
 366         .iProduct          = STR_PRODUCT,
 367         .iSerialNumber     = STR_SERIALNUMBER,
 368     },
 369     .full  = &desc_device_full,
 370     .high  = &desc_device_high,
 371     .str   = desc_strings,
 372     .msos  = &desc_msos,
 373 };
 374
 375 /* ----------------------------------------------------------------------- */
 376
 377 static MTPObject *usb_mtp_object_alloc(MTPState *s, uint32_t handle,
 378                                        MTPObject *parent, const char *name)
 379 {
 380     MTPObject *o = g_new0(MTPObject, 1);
 381
 382     if (name[0] == '.') {
 383         goto ignore;
 384     }
 385
 386     o->watchid = -1;
 387     o->handle = handle;
 388     o->parent = parent;
 389     o->name = g_strdup(name);
 390     if (parent == NULL) {
 391         o->path = g_strdup(name);
 392     } else {
 393         o->path = g_strdup_printf("%s/%s", parent->path, name);
 394     }
 395
 396     if (lstat(o->path, &o->stat) != 0) {
 397         goto ignore;
 398     }
 399     if (S_ISREG(o->stat.st_mode)) {
 400         o->format = FMT_UNDEFINED_OBJECT;
 401     } else if (S_ISDIR(o->stat.st_mode)) {
 402         o->format = FMT_ASSOCIATION;
 403     } else {
 404         goto ignore;
 405     }
 406
 407     if (access(o->path, R_OK) != 0) {
 408         goto ignore;
 409     }
 410
 411     trace_usb_mtp_object_alloc(s->dev.addr, o->handle, o->path);
 412
 413     QTAILQ_INSERT_TAIL(&s->objects, o, next);
 414     return o;
 415
 416 ignore:
 417     g_free(o->name);
 418     g_free(o->path);
 419     g_free(o);
 420     return NULL;
 421 }
 422
 423 static void usb_mtp_object_free(MTPState *s, MTPObject *o)
 424 {
 425     MTPObject *iter;
 426
 427     if (!o) {
 428         return;
 429     }
 430
 431     trace_usb_mtp_object_free(s->dev.addr, o->handle, o->path);
 432
 433     if (o->watchid != -1 && s->file_monitor) {
 434         qemu_file_monitor_remove_watch(s->file_monitor, o->path, o->watchid);
 435     }
 436
 437     QTAILQ_REMOVE(&s->objects, o, next);
 438     if (o->parent) {
 439         QLIST_REMOVE(o, list);
 440         o->parent->nchildren--;
 441     }
 442
 443     while (!QLIST_EMPTY(&o->children)) {
 444         iter = QLIST_FIRST(&o->children);
 445         usb_mtp_object_free(s, iter);
 446     }
 447     g_free(o->name);
 448     g_free(o->path);
 449     g_free(o);
 450 }
 451
 452 static MTPObject *usb_mtp_object_lookup(MTPState *s, uint32_t handle)
 453 {
 454     MTPObject *o;
 455
 456     QTAILQ_FOREACH(o, &s->objects, next) {
 457         if (o->handle == handle) {
 458             return o;
 459         }
 460     }
 461     return NULL;
 462 }
 463
 464 static MTPObject *usb_mtp_add_child(MTPState *s, MTPObject *o,
 465                                     const char *name)
 466 {
 467     MTPObject *child =
 468         usb_mtp_object_alloc(s, s->next_handle++, o, name);
 469
 470     if (child) {
 471         trace_usb_mtp_add_child(s->dev.addr, child->handle, child->path);
 472         QLIST_INSERT_HEAD(&o->children, child, list);
 473         o->nchildren++;
 474
 475         if (child->format == FMT_ASSOCIATION) {
 476             QLIST_INIT(&child->children);
 477         }
 478     }
 479
 480     return child;
 481 }
 482
 483 static MTPObject *usb_mtp_object_lookup_name(MTPObject *parent,
 484                                              const char *name, int len)
 485 {
 486     MTPObject *iter;
 487
 488     if (len == -1) {
 489         len = strlen(name);
 490     }
 491
 492     QLIST_FOREACH(iter, &parent->children, list) {
 493         if (strncmp(iter->name, name, len) == 0) {
 494             return iter;
 495         }
 496     }
 497
 498     return NULL;
 499 }
 500
 501 static MTPObject *usb_mtp_object_lookup_id(MTPState *s, int64_t id)
 502 {
 503     MTPObject *iter;
 504
 505     QTAILQ_FOREACH(iter, &s->objects, next) {
 506         if (iter->watchid == id) {
 507             return iter;
 508         }
 509     }
 510
 511     return NULL;
 512 }
 513
 514 static void file_monitor_event(int64_t id,
 515                                QFileMonitorEvent ev,
 516                                const char *name,
 517                                void *opaque)
 518 {
 519     MTPState *s = opaque;
 520     MTPObject *parent = usb_mtp_object_lookup_id(s, id);
 521     MTPMonEntry *entry = NULL;
 522     MTPObject *o;
 523
 524     if (!parent) {
 525         return;
 526     }
 527
 528     switch (ev) {
 529     case QFILE_MONITOR_EVENT_CREATED:
 530         if (usb_mtp_object_lookup_name(parent, name, -1)) {
 531             /* Duplicate create event */
 532             return;
 533         }
 534         entry = g_new0(MTPMonEntry, 1);
 535         entry->handle = s->next_handle;
 536         entry->event = EVT_OBJ_ADDED;
 537         o = usb_mtp_add_child(s, parent, name);
 538         if (!o) {
 539             g_free(entry);
 540             return;
 541         }
 542         trace_usb_mtp_file_monitor_event(s->dev.addr, name, "Obj Added");
 543         break;
 544
 545     case QFILE_MONITOR_EVENT_DELETED:
 546         /*
 547          * The kernel issues a IN_IGNORED event
 548          * when a dir containing a watchpoint is
 549          * deleted, so we don't have to delete the
 550          * watchpoint
 551          */
 552         o = usb_mtp_object_lookup_name(parent, name, -1);
 553         if (!o) {
 554             return;
 555         }
 556         entry = g_new0(MTPMonEntry, 1);
 557         entry->handle = o->handle;
 558         entry->event = EVT_OBJ_REMOVED;
 559         trace_usb_mtp_file_monitor_event(s->dev.addr, o->path, "Obj Deleted");
 560         usb_mtp_object_free(s, o);
 561         break;
 562
 563     case QFILE_MONITOR_EVENT_MODIFIED:
 564         o = usb_mtp_object_lookup_name(parent, name, -1);
 565         if (!o) {
 566             return;
 567         }
 568         entry = g_new0(MTPMonEntry, 1);
 569         entry->handle = o->handle;
 570         entry->event = EVT_OBJ_INFO_CHANGED;
 571         trace_usb_mtp_file_monitor_event(s->dev.addr, o->path, "Obj Modified");
 572         break;
 573
 574     case QFILE_MONITOR_EVENT_IGNORED:
 575         trace_usb_mtp_file_monitor_event(s->dev.addr, parent->path,
 576                                     "Obj parent dir ignored");
 577         break;
 578
 579     case QFILE_MONITOR_EVENT_ATTRIBUTES:
 580         break;
 581
 582     default:
 583         g_assert_not_reached();
 584     }
 585
 586     if (entry) {
 587         QTAILQ_INSERT_HEAD(&s->events, entry, next);
 588     }
 589 }
 590
 591 static void usb_mtp_file_monitor_cleanup(MTPState *s)
 592 {
 593     MTPMonEntry *e, *p;
 594
 595     QTAILQ_FOREACH_SAFE(e, &s->events, next, p) {
 596         QTAILQ_REMOVE(&s->events, e, next);
 597         g_free(e);
 598     }
 599
 600     qemu_file_monitor_free(s->file_monitor);
 601     s->file_monitor = NULL;
 602 }
 603
 604
 605 static void usb_mtp_object_readdir(MTPState *s, MTPObject *o)
 606 {
 607     struct dirent *entry;
 608     DIR *dir;
 609     int fd;
 610     Error *err = NULL;
 611
 612     if (o->have_children) {
 613         return;
 614     }
 615     o->have_children = true;
 616
 617     fd = open(o->path, O_DIRECTORY | O_CLOEXEC | O_NOFOLLOW);
 618     if (fd < 0) {
 619         return;
 620     }
 621     dir = fdopendir(fd);
 622     if (!dir) {
 623         close(fd);
 624         return;
 625     }
 626
 627     if (s->file_monitor) {
 628         int64_t id = qemu_file_monitor_add_watch(s->file_monitor, o->path, NULL,
 629                                                  file_monitor_event, s, &err);
 630         if (id == -1) {
 631             error_report("usb-mtp: failed to add watch for %s: %s", o->path,
 632                          error_get_pretty(err));
 633             error_free(err);
 634         } else {
 635             trace_usb_mtp_file_monitor_event(s->dev.addr, o->path,
 636                                              "Watch Added");
 637             o->watchid = id;
 638         }
 639     }
 640
 641     while ((entry = readdir(dir)) != NULL) {
 642         usb_mtp_add_child(s, o, entry->d_name);
 643     }
 644     closedir(dir);
 645 }
 646
 647 /* ----------------------------------------------------------------------- */
 648
 649 static MTPData *usb_mtp_data_alloc(MTPControl *c)
 650 {
 651     MTPData *data = g_new0(MTPData, 1);
 652
 653     data->code  = c->code;
 654     data->trans = c->trans;
 655     data->fd    = -1;
 656     data->first = true;
 657     return data;
 658 }
 659
 660 static void usb_mtp_data_free(MTPData *data)
 661 {
 662     if (data == NULL) {
 663         return;
 664     }
 665     if (data->fd != -1) {
 666         close(data->fd);
 667     }
 668     g_free(data->data);
 669     g_free(data);
 670 }
 671
 672 static void usb_mtp_realloc(MTPData *data, uint32_t bytes)
 673 {
 674     if (data->length + bytes <= data->alloc) {
 675         return;
 676     }
 677     data->alloc = (data->length + bytes + 0xff) & ~0xff;
 678     data->data  = g_realloc(data->data, data->alloc);
 679 }
 680
 681 static void usb_mtp_add_u8(MTPData *data, uint8_t val)
 682 {
 683     usb_mtp_realloc(data, 1);
 684     data->data[data->length++] = val;
 685 }
 686
 687 static void usb_mtp_add_u16(MTPData *data, uint16_t val)
 688 {
 689     usb_mtp_realloc(data, 2);
 690     data->data[data->length++] = (val >> 0) & 0xff;
 691     data->data[data->length++] = (val >> 8) & 0xff;
 692 }
 693
 694 static void usb_mtp_add_u32(MTPData *data, uint32_t val)
 695 {
 696     usb_mtp_realloc(data, 4);
 697     data->data[data->length++] = (val >>  0) & 0xff;
 698     data->data[data->length++] = (val >>  8) & 0xff;
 699     data->data[data->length++] = (val >> 16) & 0xff;
 700     data->data[data->length++] = (val >> 24) & 0xff;
 701 }
 702
 703 static void usb_mtp_add_u64(MTPData *data, uint64_t val)
 704 {
 705     usb_mtp_realloc(data, 8);
 706     data->data[data->length++] = (val >>  0) & 0xff;
 707     data->data[data->length++] = (val >>  8) & 0xff;
 708     data->data[data->length++] = (val >> 16) & 0xff;
 709     data->data[data->length++] = (val >> 24) & 0xff;
 710     data->data[data->length++] = (val >> 32) & 0xff;
 711     data->data[data->length++] = (val >> 40) & 0xff;
 712     data->data[data->length++] = (val >> 48) & 0xff;
 713     data->data[data->length++] = (val >> 56) & 0xff;
 714 }
 715
 716 static void usb_mtp_add_u16_array(MTPData *data, uint32_t len,
 717                                   const uint16_t *vals)
 718 {
 719     int i;
 720
 721     usb_mtp_add_u32(data, len);
 722     for (i = 0; i < len; i++) {
 723         usb_mtp_add_u16(data, vals[i]);
 724     }
 725 }
 726
 727 static void usb_mtp_add_u32_array(MTPData *data, uint32_t len,
 728                                   const uint32_t *vals)
 729 {
 730     int i;
 731
 732     usb_mtp_add_u32(data, len);
 733     for (i = 0; i < len; i++) {
 734         usb_mtp_add_u32(data, vals[i]);
 735     }
 736 }
 737
 738 static void usb_mtp_add_wstr(MTPData *data, const wchar_t *str)
 739 {
 740     uint32_t len = wcslen(str);
 741     int i;
 742
 743     if (len > 0) {
 744         len++; /* include terminating L'\0' */
 745     }
 746
 747     usb_mtp_add_u8(data, len);
 748     for (i = 0; i < len; i++) {
 749         usb_mtp_add_u16(data, str[i]);
 750     }
 751 }
 752
 753 static void usb_mtp_add_str(MTPData *data, const char *str)
 754 {
 755     uint32_t len = strlen(str)+1;
 756     wchar_t *wstr = g_new(wchar_t, len);
 757     size_t ret;
 758
 759     ret = mbstowcs(wstr, str, len);
 760     if (ret == -1) {
 761         usb_mtp_add_wstr(data, L"Oops");
 762     } else {
 763         usb_mtp_add_wstr(data, wstr);
 764     }
 765
 766     g_free(wstr);
 767 }
 768
 769 static void usb_mtp_add_time(MTPData *data, time_t time)
 770 {
 771     char buf[16];
 772     struct tm tm;
 773
 774     gmtime_r(&time, &tm);
 775     strftime(buf, sizeof(buf), "%Y%m%dT%H%M%S", &tm);
 776     usb_mtp_add_str(data, buf);
 777 }
 778
 779 /* ----------------------------------------------------------------------- */
 780
 781 static void usb_mtp_queue_result(MTPState *s, uint16_t code, uint32_t trans,
 782                                  int argc, uint32_t arg0, uint32_t arg1,
 783                                  uint32_t arg2)
 784 {
 785     MTPControl *c = g_new0(MTPControl, 1);
 786
 787     c->code  = code;
 788     c->trans = trans;
 789     c->argc  = argc;
 790     if (argc > 0) {
 791         c->argv[0] = arg0;
 792     }
 793     if (argc > 1) {
 794         c->argv[1] = arg1;
 795     }
 796     if (argc > 2) {
 797         c->argv[2] = arg2;
 798     }
 799
 800     assert(s->result == NULL);
 801     s->result = c;
 802 }
 803
 804 /* ----------------------------------------------------------------------- */
 805
 806 static MTPData *usb_mtp_get_device_info(MTPState *s, MTPControl *c)
 807 {
 808     static const uint16_t ops[] = {
 809         CMD_GET_DEVICE_INFO,
 810         CMD_OPEN_SESSION,
 811         CMD_CLOSE_SESSION,
 812         CMD_GET_STORAGE_IDS,
 813         CMD_GET_STORAGE_INFO,
 814         CMD_GET_NUM_OBJECTS,
 815         CMD_GET_OBJECT_HANDLES,
 816         CMD_GET_OBJECT_INFO,
 817         CMD_DELETE_OBJECT,
 818         CMD_SEND_OBJECT_INFO,
 819         CMD_SEND_OBJECT,
 820         CMD_GET_OBJECT,
 821         CMD_GET_PARTIAL_OBJECT,
 822         CMD_GET_OBJECT_PROPS_SUPPORTED,
 823         CMD_GET_OBJECT_PROP_DESC,
 824         CMD_GET_OBJECT_PROP_VALUE,
 825     };
 826     static const uint16_t fmt[] = {
 827         FMT_UNDEFINED_OBJECT,
 828         FMT_ASSOCIATION,
 829     };
 830     MTPData *d = usb_mtp_data_alloc(c);
 831
 832     trace_usb_mtp_op_get_device_info(s->dev.addr);
 833
 834     usb_mtp_add_u16(d, 100);
 835     usb_mtp_add_u32(d, 0x00000006);
 836     usb_mtp_add_u16(d, 0x0064);
 837     usb_mtp_add_wstr(d, L"");
 838     usb_mtp_add_u16(d, 0x0000);
 839
 840     usb_mtp_add_u16_array(d, ARRAY_SIZE(ops), ops);
 841     usb_mtp_add_u16_array(d, 0, NULL);
 842     usb_mtp_add_u16_array(d, 0, NULL);
 843     usb_mtp_add_u16_array(d, 0, NULL);
 844     usb_mtp_add_u16_array(d, ARRAY_SIZE(fmt), fmt);
 845
 846     usb_mtp_add_wstr(d, L"" MTP_MANUFACTURER);
 847     usb_mtp_add_wstr(d, L"" MTP_PRODUCT);
 848     usb_mtp_add_wstr(d, L"0.1");
 849     usb_mtp_add_wstr(d, L"0123456789abcdef0123456789abcdef");
 850
 851     return d;
 852 }
 853
 854 static MTPData *usb_mtp_get_storage_ids(MTPState *s, MTPControl *c)
 855 {
 856     static const uint32_t ids[] = {
 857         QEMU_STORAGE_ID,
 858     };
 859     MTPData *d = usb_mtp_data_alloc(c);
 860
 861     trace_usb_mtp_op_get_storage_ids(s->dev.addr);
 862
 863     usb_mtp_add_u32_array(d, ARRAY_SIZE(ids), ids);
 864
 865     return d;
 866 }
 867
 868 static MTPData *usb_mtp_get_storage_info(MTPState *s, MTPControl *c)
 869 {
 870     MTPData *d = usb_mtp_data_alloc(c);
 871     struct statvfs buf;
 872     int rc;
 873
 874     trace_usb_mtp_op_get_storage_info(s->dev.addr);
 875
 876     if (FLAG_SET(s, MTP_FLAG_WRITABLE)) {
 877         usb_mtp_add_u16(d, 0x0003);
 878         usb_mtp_add_u16(d, 0x0002);
 879         usb_mtp_add_u16(d, 0x0000);
 880     } else {
 881         usb_mtp_add_u16(d, 0x0001);
 882         usb_mtp_add_u16(d, 0x0002);
 883         usb_mtp_add_u16(d, 0x0001);
 884     }
 885
 886     rc = statvfs(s->root, &buf);
 887     if (rc == 0) {
 888         usb_mtp_add_u64(d, (uint64_t)buf.f_frsize * buf.f_blocks);
 889         usb_mtp_add_u64(d, (uint64_t)buf.f_bavail * buf.f_blocks);
 890         usb_mtp_add_u32(d, buf.f_ffree);
 891     } else {
 892         usb_mtp_add_u64(d, 0xffffffff);
 893         usb_mtp_add_u64(d, 0xffffffff);
 894         usb_mtp_add_u32(d, 0xffffffff);
 895     }
 896
 897     usb_mtp_add_str(d, s->desc);
 898     usb_mtp_add_wstr(d, L"123456789abcdef");
 899     return d;
 900 }
 901
 902 static MTPData *usb_mtp_get_object_handles(MTPState *s, MTPControl *c,
 903                                            MTPObject *o)
 904 {
 905     MTPData *d = usb_mtp_data_alloc(c);
 906     uint32_t i = 0, handles[o->nchildren];
 907     MTPObject *iter;
 908
 909     trace_usb_mtp_op_get_object_handles(s->dev.addr, o->handle, o->path);
 910
 911     QLIST_FOREACH(iter, &o->children, list) {
 912         handles[i++] = iter->handle;
 913     }
 914     assert(i == o->nchildren);
 915     usb_mtp_add_u32_array(d, o->nchildren, handles);
 916
 917     return d;
 918 }
 919
 920 static MTPData *usb_mtp_get_object_info(MTPState *s, MTPControl *c,
 921                                         MTPObject *o)
 922 {
 923     MTPData *d = usb_mtp_data_alloc(c);
 924
 925     trace_usb_mtp_op_get_object_info(s->dev.addr, o->handle, o->path);
 926
 927     usb_mtp_add_u32(d, QEMU_STORAGE_ID);
 928     usb_mtp_add_u16(d, o->format);
 929     usb_mtp_add_u16(d, 0);
 930
 931     if (o->stat.st_size > 0xFFFFFFFF) {
 932         usb_mtp_add_u32(d, 0xFFFFFFFF);
 933     } else {
 934         usb_mtp_add_u32(d, o->stat.st_size);
 935     }
 936
 937     usb_mtp_add_u16(d, 0);
 938     usb_mtp_add_u32(d, 0);
 939     usb_mtp_add_u32(d, 0);
 940     usb_mtp_add_u32(d, 0);
 941     usb_mtp_add_u32(d, 0);
 942     usb_mtp_add_u32(d, 0);
 943     usb_mtp_add_u32(d, 0);
 944
 945     if (o->parent) {
 946         usb_mtp_add_u32(d, o->parent->handle);
 947     } else {
 948         usb_mtp_add_u32(d, 0);
 949     }
 950     if (o->format == FMT_ASSOCIATION) {
 951         usb_mtp_add_u16(d, 0x0001);
 952         usb_mtp_add_u32(d, 0x00000001);
 953         usb_mtp_add_u32(d, 0);
 954     } else {
 955         usb_mtp_add_u16(d, 0);
 956         usb_mtp_add_u32(d, 0);
 957         usb_mtp_add_u32(d, 0);
 958     }
 959
 960     usb_mtp_add_str(d, o->name);
 961     usb_mtp_add_time(d, o->stat.st_ctime);
 962     usb_mtp_add_time(d, o->stat.st_mtime);
 963     usb_mtp_add_wstr(d, L"");
 964
 965     return d;
 966 }
 967
 968 static MTPData *usb_mtp_get_object(MTPState *s, MTPControl *c,
 969                                    MTPObject *o)
 970 {
 971     MTPData *d = usb_mtp_data_alloc(c);
 972
 973     trace_usb_mtp_op_get_object(s->dev.addr, o->handle, o->path);
 974
 975     d->fd = open(o->path, O_RDONLY | O_CLOEXEC | O_NOFOLLOW);
 976     if (d->fd == -1) {
 977         usb_mtp_data_free(d);
 978         return NULL;
 979     }
 980     d->length = o->stat.st_size;
 981     d->alloc  = 512;
 982     d->data   = g_malloc(d->alloc);
 983     return d;
 984 }
 985
 986 static MTPData *usb_mtp_get_partial_object(MTPState *s, MTPControl *c,
 987                                            MTPObject *o)
 988 {
 989     MTPData *d;
 990     off_t offset;
 991
 992     if (c->argc <= 2) {
 993         return NULL;
 994     }
 995     trace_usb_mtp_op_get_partial_object(s->dev.addr, o->handle, o->path,
 996                                         c->argv[1], c->argv[2]);
 997
 998     d = usb_mtp_data_alloc(c);
 999     d->fd = open(o->path, O_RDONLY | O_CLOEXEC | O_NOFOLLOW);
1000     if (d->fd == -1) {
1001         usb_mtp_data_free(d);
1002         return NULL;
1003     }
1004
1005     offset = c->argv[1];
1006     if (offset > o->stat.st_size) {
1007         offset = o->stat.st_size;
1008     }
1009     if (lseek(d->fd, offset, SEEK_SET) < 0) {
1010         usb_mtp_data_free(d);
1011         return NULL;
1012     }
1013
1014     d->length = c->argv[2];
1015     if (d->length > o->stat.st_size - offset) {
1016         d->length = o->stat.st_size - offset;
1017     }
1018
1019     return d;
1020 }
1021
1022 static MTPData *usb_mtp_get_object_props_supported(MTPState *s, MTPControl *c)
1023 {
1024     static const uint16_t props[] = {
1025         PROP_STORAGE_ID,
1026         PROP_OBJECT_FORMAT,
1027         PROP_OBJECT_COMPRESSED_SIZE,
1028         PROP_PARENT_OBJECT,
1029         PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER,
1030         PROP_NAME,
1031     };
1032     MTPData *d = usb_mtp_data_alloc(c);
1033     usb_mtp_add_u16_array(d, ARRAY_SIZE(props), props);
1034
1035     return d;
1036 }
1037
1038 static MTPData *usb_mtp_get_object_prop_desc(MTPState *s, MTPControl *c)
1039 {
1040     MTPData *d = usb_mtp_data_alloc(c);
1041     switch (c->argv[0]) {
1042     case PROP_STORAGE_ID:
1043         usb_mtp_add_u16(d, PROP_STORAGE_ID);
1044         usb_mtp_add_u16(d, DATA_TYPE_UINT32);
1045         usb_mtp_add_u8(d, 0x00);
1046         usb_mtp_add_u32(d, 0x00000000);
1047         usb_mtp_add_u32(d, 0x00000000);
1048         usb_mtp_add_u8(d, 0x00);
1049         break;
1050     case PROP_OBJECT_FORMAT:
1051         usb_mtp_add_u16(d, PROP_OBJECT_FORMAT);
1052         usb_mtp_add_u16(d, DATA_TYPE_UINT16);
1053         usb_mtp_add_u8(d, 0x00);
1054         usb_mtp_add_u16(d, 0x0000);
1055         usb_mtp_add_u32(d, 0x00000000);
1056         usb_mtp_add_u8(d, 0x00);
1057         break;
1058     case PROP_OBJECT_COMPRESSED_SIZE:
1059         usb_mtp_add_u16(d, PROP_OBJECT_COMPRESSED_SIZE);
1060         usb_mtp_add_u16(d, DATA_TYPE_UINT64);
1061         usb_mtp_add_u8(d, 0x00);
1062         usb_mtp_add_u64(d, 0x0000000000000000);
1063         usb_mtp_add_u32(d, 0x00000000);
1064         usb_mtp_add_u8(d, 0x00);
1065         break;
1066     case PROP_PARENT_OBJECT:
1067         usb_mtp_add_u16(d, PROP_PARENT_OBJECT);
1068         usb_mtp_add_u16(d, DATA_TYPE_UINT32);
1069         usb_mtp_add_u8(d, 0x00);
1070         usb_mtp_add_u32(d, 0x00000000);
1071         usb_mtp_add_u32(d, 0x00000000);
1072         usb_mtp_add_u8(d, 0x00);
1073         break;
1074     case PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER:
1075         usb_mtp_add_u16(d, PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER);
1076         usb_mtp_add_u16(d, DATA_TYPE_UINT128);
1077         usb_mtp_add_u8(d, 0x00);
1078         usb_mtp_add_u64(d, 0x0000000000000000);
1079         usb_mtp_add_u64(d, 0x0000000000000000);
1080         usb_mtp_add_u32(d, 0x00000000);
1081         usb_mtp_add_u8(d, 0x00);
1082         break;
1083     case PROP_NAME:
1084         usb_mtp_add_u16(d, PROP_NAME);
1085         usb_mtp_add_u16(d, DATA_TYPE_STRING);
1086         usb_mtp_add_u8(d, 0x00);
1087         usb_mtp_add_u8(d, 0x00);
1088         usb_mtp_add_u32(d, 0x00000000);
1089         usb_mtp_add_u8(d, 0x00);
1090         break;
1091     default:
1092         usb_mtp_data_free(d);
1093         return NULL;
1094     }
1095
1096     return d;
1097 }
1098
1099 static MTPData *usb_mtp_get_object_prop_value(MTPState *s, MTPControl *c,
1100                                               MTPObject *o)
1101 {
1102     MTPData *d = usb_mtp_data_alloc(c);
1103     switch (c->argv[1]) {
1104     case PROP_STORAGE_ID:
1105         usb_mtp_add_u32(d, QEMU_STORAGE_ID);
1106         break;
1107     case PROP_OBJECT_FORMAT:
1108         usb_mtp_add_u16(d, o->format);
1109         break;
1110     case PROP_OBJECT_COMPRESSED_SIZE:
1111         usb_mtp_add_u64(d, o->stat.st_size);
1112         break;
1113     case PROP_PARENT_OBJECT:
1114         if (o->parent == NULL) {
1115             usb_mtp_add_u32(d, 0x00000000);
1116         } else {
1117             usb_mtp_add_u32(d, o->parent->handle);
1118         }
1119         break;
1120     case PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER:
1121         /* Should be persistent between sessions,
1122          * but using our objedt ID is "good enough"
1123          * for now */
1124         usb_mtp_add_u64(d, 0x0000000000000000);
1125         usb_mtp_add_u64(d, o->handle);
1126         break;
1127     case PROP_NAME:
1128         usb_mtp_add_str(d, o->name);
1129         break;
1130     default:
1131         usb_mtp_data_free(d);
1132         return NULL;
1133     }
1134
1135     return d;
1136 }
1137
1138 /*
1139  * Return values when object @o is deleted.
1140  * If at least one of the deletions succeeded,
1141  * DELETE_SUCCESS is set and if at least one
1142  * of the deletions failed, DELETE_FAILURE is
1143  * set. Both bits being set (DELETE_PARTIAL)
1144  * signifies a  RES_PARTIAL_DELETE being sent
1145  * back to the initiator.
1146  */
1147 enum {
1148     DELETE_SUCCESS = (1 << 0),
1149     DELETE_FAILURE = (1 << 1),
1150     DELETE_PARTIAL = (DELETE_FAILURE | DELETE_SUCCESS),
1151 };
1152
1153 static int usb_mtp_deletefn(MTPState *s, MTPObject *o, uint32_t trans)
1154 {
1155     MTPObject *iter, *iter2;
1156     int ret = 0;
1157
1158     /*
1159      * TODO: Add support for Protection Status
1160      */
1161
1162     QLIST_FOREACH(iter, &o->children, list) {
1163         if (iter->format == FMT_ASSOCIATION) {
1164             QLIST_FOREACH(iter2, &iter->children, list) {
1165                 ret |= usb_mtp_deletefn(s, iter2, trans);
1166             }
1167         }
1168     }
1169
1170     if (o->format == FMT_UNDEFINED_OBJECT) {
1171         if (remove(o->path)) {
1172             ret |= DELETE_FAILURE;
1173         } else {
1174             usb_mtp_object_free(s, o);
1175             ret |= DELETE_SUCCESS;
1176         }
1177     } else if (o->format == FMT_ASSOCIATION) {
1178         if (rmdir(o->path)) {
1179             ret |= DELETE_FAILURE;
1180         } else {
1181             usb_mtp_object_free(s, o);
1182             ret |= DELETE_SUCCESS;
1183         }
1184     }
1185
1186     return ret;
1187 }
1188
1189 static void usb_mtp_object_delete(MTPState *s, uint32_t handle,
1190                                   uint32_t format_code, uint32_t trans)
1191 {
1192     MTPObject *o;
1193     int ret;
1194
1195     /* Return error if store is read-only */
1196     if (!FLAG_SET(s, MTP_FLAG_WRITABLE)) {
1197         usb_mtp_queue_result(s, RES_STORE_READ_ONLY,
1198                              trans, 0, 0, 0, 0);
1199         return;
1200     }
1201
1202     if (format_code != 0) {
1203         usb_mtp_queue_result(s, RES_SPEC_BY_FORMAT_UNSUPPORTED,
1204                              trans, 0, 0, 0, 0);
1205         return;
1206     }
1207
1208     if (handle == 0xFFFFFFF) {
1209         o = QTAILQ_FIRST(&s->objects);
1210     } else {
1211         o = usb_mtp_object_lookup(s, handle);
1212     }
1213     if (o == NULL) {
1214         usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1215                              trans, 0, 0, 0, 0);
1216         return;
1217     }
1218
1219     ret = usb_mtp_deletefn(s, o, trans);
1220     switch (ret) {
1221     case DELETE_SUCCESS:
1222         usb_mtp_queue_result(s, RES_OK, trans,
1223                              0, 0, 0, 0);
1224         break;
1225     case DELETE_FAILURE:
1226         usb_mtp_queue_result(s, RES_PARTIAL_DELETE,
1227                              trans, 0, 0, 0, 0);
1228         break;
1229     case DELETE_PARTIAL:
1230         usb_mtp_queue_result(s, RES_PARTIAL_DELETE,
1231                              trans, 0, 0, 0, 0);
1232         break;
1233     default:
1234         g_assert_not_reached();
1235     }
1236
1237     return;
1238 }
1239
1240 static void usb_mtp_command(MTPState *s, MTPControl *c)
1241 {
1242     MTPData *data_in = NULL;
1243     MTPObject *o = NULL;
1244     uint32_t nres = 0, res0 = 0;
1245     Error *err = NULL;
1246
1247     /* sanity checks */
1248     if (c->code >= CMD_CLOSE_SESSION && s->session == 0) {
1249         usb_mtp_queue_result(s, RES_SESSION_NOT_OPEN,
1250                              c->trans, 0, 0, 0, 0);
1251         return;
1252     }
1253
1254     /* process commands */
1255     switch (c->code) {
1256     case CMD_GET_DEVICE_INFO:
1257         data_in = usb_mtp_get_device_info(s, c);
1258         break;
1259     case CMD_OPEN_SESSION:
1260         if (s->session) {
1261             usb_mtp_queue_result(s, RES_SESSION_ALREADY_OPEN,
1262                                  c->trans, 1, s->session, 0, 0);
1263             return;
1264         }
1265         if (c->argv[0] == 0) {
1266             usb_mtp_queue_result(s, RES_INVALID_PARAMETER,
1267                                  c->trans, 0, 0, 0, 0);
1268             return;
1269         }
1270         trace_usb_mtp_op_open_session(s->dev.addr);
1271         s->session = c->argv[0];
1272         usb_mtp_object_alloc(s, s->next_handle++, NULL, s->root);
1273
1274         s->file_monitor = qemu_file_monitor_new(&err);
1275         if (err) {
1276             error_report("usb-mtp: file monitoring init failed: %s",
1277                          error_get_pretty(err));
1278             error_free(err);
1279         } else {
1280             QTAILQ_INIT(&s->events);
1281         }
1282         break;
1283     case CMD_CLOSE_SESSION:
1284         trace_usb_mtp_op_close_session(s->dev.addr);
1285         s->session = 0;
1286         s->next_handle = 0;
1287         usb_mtp_file_monitor_cleanup(s);
1288         usb_mtp_object_free(s, QTAILQ_FIRST(&s->objects));
1289         assert(QTAILQ_EMPTY(&s->objects));
1290         break;
1291     case CMD_GET_STORAGE_IDS:
1292         data_in = usb_mtp_get_storage_ids(s, c);
1293         break;
1294     case CMD_GET_STORAGE_INFO:
1295         if (c->argv[0] != QEMU_STORAGE_ID &&
1296             c->argv[0] != 0xffffffff) {
1297             usb_mtp_queue_result(s, RES_INVALID_STORAGE_ID,
1298                                  c->trans, 0, 0, 0, 0);
1299             return;
1300         }
1301         data_in = usb_mtp_get_storage_info(s, c);
1302         break;
1303     case CMD_GET_NUM_OBJECTS:
1304     case CMD_GET_OBJECT_HANDLES:
1305         if (c->argv[0] != QEMU_STORAGE_ID &&
1306             c->argv[0] != 0xffffffff) {
1307             usb_mtp_queue_result(s, RES_INVALID_STORAGE_ID,
1308                                  c->trans, 0, 0, 0, 0);
1309             return;
1310         }
1311         if (c->argv[1] != 0x00000000) {
1312             usb_mtp_queue_result(s, RES_SPEC_BY_FORMAT_UNSUPPORTED,
1313                                  c->trans, 0, 0, 0, 0);
1314             return;
1315         }
1316         if (c->argv[2] == 0x00000000 ||
1317             c->argv[2] == 0xffffffff) {
1318             o = QTAILQ_FIRST(&s->objects);
1319         } else {
1320             o = usb_mtp_object_lookup(s, c->argv[2]);
1321         }
1322         if (o == NULL) {
1323             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1324                                  c->trans, 0, 0, 0, 0);
1325             return;
1326         }
1327         if (o->format != FMT_ASSOCIATION) {
1328             usb_mtp_queue_result(s, RES_INVALID_PARENT_OBJECT,
1329                                  c->trans, 0, 0, 0, 0);
1330             return;
1331         }
1332         usb_mtp_object_readdir(s, o);
1333         if (c->code == CMD_GET_NUM_OBJECTS) {
1334             trace_usb_mtp_op_get_num_objects(s->dev.addr, o->handle, o->path);
1335             nres = 1;
1336             res0 = o->nchildren;
1337         } else {
1338             data_in = usb_mtp_get_object_handles(s, c, o);
1339         }
1340         break;
1341     case CMD_GET_OBJECT_INFO:
1342         o = usb_mtp_object_lookup(s, c->argv[0]);
1343         if (o == NULL) {
1344             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1345                                  c->trans, 0, 0, 0, 0);
1346             return;
1347         }
1348         data_in = usb_mtp_get_object_info(s, c, o);
1349         break;
1350     case CMD_GET_OBJECT:
1351         o = usb_mtp_object_lookup(s, c->argv[0]);
1352         if (o == NULL) {
1353             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1354                                  c->trans, 0, 0, 0, 0);
1355             return;
1356         }
1357         if (o->format == FMT_ASSOCIATION) {
1358             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1359                                  c->trans, 0, 0, 0, 0);
1360             return;
1361         }
1362         data_in = usb_mtp_get_object(s, c, o);
1363         if (data_in == NULL) {
1364             usb_mtp_queue_result(s, RES_GENERAL_ERROR,
1365                                  c->trans, 0, 0, 0, 0);
1366             return;
1367         }
1368         break;
1369     case CMD_DELETE_OBJECT:
1370         usb_mtp_object_delete(s, c->argv[0], c->argv[1], c->trans);
1371         return;
1372     case CMD_GET_PARTIAL_OBJECT:
1373         o = usb_mtp_object_lookup(s, c->argv[0]);
1374         if (o == NULL) {
1375             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1376                                  c->trans, 0, 0, 0, 0);
1377             return;
1378         }
1379         if (o->format == FMT_ASSOCIATION) {
1380             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1381                                  c->trans, 0, 0, 0, 0);
1382             return;
1383         }
1384         data_in = usb_mtp_get_partial_object(s, c, o);
1385         if (data_in == NULL) {
1386             usb_mtp_queue_result(s, RES_GENERAL_ERROR,
1387                                  c->trans, 0, 0, 0, 0);
1388             return;
1389         }
1390         nres = 1;
1391         res0 = data_in->length;
1392         break;
1393     case CMD_SEND_OBJECT_INFO:
1394         /* Return error if store is read-only */
1395         if (!FLAG_SET(s, MTP_FLAG_WRITABLE)) {
1396             usb_mtp_queue_result(s, RES_STORE_READ_ONLY,
1397                                  c->trans, 0, 0, 0, 0);
1398         } else if (c->argv[0] && (c->argv[0] != QEMU_STORAGE_ID)) {
1399             /* First parameter points to storage id or is 0 */
1400             usb_mtp_queue_result(s, RES_STORE_NOT_AVAILABLE, c->trans,
1401                                  0, 0, 0, 0);
1402         } else if (c->argv[1] && !c->argv[0]) {
1403             /* If second parameter is specified, first must also be specified */
1404             usb_mtp_queue_result(s, RES_DESTINATION_UNSUPPORTED, c->trans,
1405                                  0, 0, 0, 0);
1406         } else {
1407             uint32_t handle = c->argv[1];
1408             if (handle == 0xFFFFFFFF || handle == 0) {
1409                 /* root object */
1410                 o = QTAILQ_FIRST(&s->objects);
1411             } else {
1412                 o = usb_mtp_object_lookup(s, handle);
1413             }
1414             if (o == NULL) {
1415                 usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE, c->trans,
1416                                      0, 0, 0, 0);
1417             } else if (o->format != FMT_ASSOCIATION) {
1418                 usb_mtp_queue_result(s, RES_INVALID_PARENT_OBJECT, c->trans,
1419                                      0, 0, 0, 0);
1420             }
1421         }
1422         if (o) {
1423             s->dataset.parent_handle = o->handle;
1424         }
1425         s->data_out = usb_mtp_data_alloc(c);
1426         return;
1427     case CMD_SEND_OBJECT:
1428         if (!FLAG_SET(s, MTP_FLAG_WRITABLE)) {
1429             usb_mtp_queue_result(s, RES_STORE_READ_ONLY,
1430                                  c->trans, 0, 0, 0, 0);
1431             return;
1432         }
1433         if (!s->write_pending) {
1434             usb_mtp_queue_result(s, RES_INVALID_OBJECTINFO,
1435                                  c->trans, 0, 0, 0, 0);
1436             return;
1437         }
1438         s->data_out = usb_mtp_data_alloc(c);
1439         return;
1440     case CMD_GET_OBJECT_PROPS_SUPPORTED:
1441         if (c->argv[0] != FMT_UNDEFINED_OBJECT &&
1442             c->argv[0] != FMT_ASSOCIATION) {
1443             usb_mtp_queue_result(s, RES_INVALID_OBJECT_FORMAT_CODE,
1444                                  c->trans, 0, 0, 0, 0);
1445             return;
1446         }
1447         data_in = usb_mtp_get_object_props_supported(s, c);
1448         break;
1449     case CMD_GET_OBJECT_PROP_DESC:
1450         if (c->argv[1] != FMT_UNDEFINED_OBJECT &&
1451             c->argv[1] != FMT_ASSOCIATION) {
1452             usb_mtp_queue_result(s, RES_INVALID_OBJECT_FORMAT_CODE,
1453                                  c->trans, 0, 0, 0, 0);
1454             return;
1455         }
1456         data_in = usb_mtp_get_object_prop_desc(s, c);
1457         if (data_in == NULL) {
1458             usb_mtp_queue_result(s, RES_INVALID_OBJECT_PROP_CODE,
1459                                  c->trans, 0, 0, 0, 0);
1460             return;
1461         }
1462         break;
1463     case CMD_GET_OBJECT_PROP_VALUE:
1464         o = usb_mtp_object_lookup(s, c->argv[0]);
1465         if (o == NULL) {
1466             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1467                                  c->trans, 0, 0, 0, 0);
1468             return;
1469         }
1470         data_in = usb_mtp_get_object_prop_value(s, c, o);
1471         if (data_in == NULL) {
1472             usb_mtp_queue_result(s, RES_INVALID_OBJECT_PROP_CODE,
1473                                  c->trans, 0, 0, 0, 0);
1474             return;
1475         }
1476         break;
1477     default:
1478         trace_usb_mtp_op_unknown(s->dev.addr, c->code);
1479         usb_mtp_queue_result(s, RES_OPERATION_NOT_SUPPORTED,
1480                              c->trans, 0, 0, 0, 0);
1481         return;
1482     }
1483
1484     /* return results on success */
1485     if (data_in) {
1486         assert(s->data_in == NULL);
1487         s->data_in = data_in;
1488     }
1489     usb_mtp_queue_result(s, RES_OK, c->trans, nres, res0, 0, 0);
1490 }
1491
1492 /* ----------------------------------------------------------------------- */
1493
1494 static void usb_mtp_handle_reset(USBDevice *dev)
1495 {
1496     MTPState *s = USB_MTP(dev);
1497
1498     trace_usb_mtp_reset(s->dev.addr);
1499
1500     usb_mtp_file_monitor_cleanup(s);
1501     usb_mtp_object_free(s, QTAILQ_FIRST(&s->objects));
1502     s->session = 0;
1503     usb_mtp_data_free(s->data_in);
1504     s->data_in = NULL;
1505     usb_mtp_data_free(s->data_out);
1506     s->data_out = NULL;
1507     g_free(s->result);
1508     s->result = NULL;
1509 }
1510
1511 static void usb_mtp_handle_control(USBDevice *dev, USBPacket *p,
1512                                    int request, int value, int index,
1513                                    int length, uint8_t *data)
1514 {
1515     int ret;
1516     MTPState *s = USB_MTP(dev);
1517     uint16_t *event = (uint16_t *)data;
1518
1519     switch (request) {
1520     case ClassInterfaceOutRequest | 0x64:
1521         if (*event == EVT_CANCEL_TRANSACTION) {
1522             g_free(s->result);
1523             s->result = NULL;
1524             usb_mtp_data_free(s->data_in);
1525             s->data_in = NULL;
1526             if (s->write_pending) {
1527                 g_free(s->dataset.filename);
1528                 s->write_pending = false;
1529                 s->dataset.size = 0;
1530             }
1531             usb_mtp_data_free(s->data_out);
1532             s->data_out = NULL;
1533         } else {
1534             p->status = USB_RET_STALL;
1535         }
1536         break;
1537     default:
1538         ret = usb_desc_handle_control(dev, p, request,
1539                                       value, index, length, data);
1540         if (ret >= 0) {
1541             return;
1542         }
1543     }
1544
1545     trace_usb_mtp_stall(dev->addr, "unknown control request");
1546 }
1547
1548 static void usb_mtp_cancel_packet(USBDevice *dev, USBPacket *p)
1549 {
1550     /* we don't use async packets, so this should never be called */
1551     fprintf(stderr, "%s\n", __func__);
1552 }
1553
1554 static char *utf16_to_str(uint8_t len, uint8_t *str16)
1555 {
1556     wchar_t *wstr = g_new0(wchar_t, len + 1);
1557     int count, dlen;
1558     char *dest;
1559
1560     for (count = 0; count < len; count++) {
1561         /* FIXME: not working for surrogate pairs */
1562         wstr[count] = lduw_le_p(str16 + (count * 2));
1563     }
1564     wstr[count] = 0;
1565
1566     dlen = wcstombs(NULL, wstr, 0) + 1;
1567     dest = g_malloc(dlen);
1568     wcstombs(dest, wstr, dlen);
1569     g_free(wstr);
1570     return dest;
1571 }
1572
1573 /* Wrapper around write, returns 0 on failure */
1574 static uint64_t write_retry(int fd, void *buf, uint64_t size, off_t offset)
1575 {
1576         uint64_t ret = 0;
1577
1578         if (lseek(fd, offset, SEEK_SET) < 0) {
1579             goto done;
1580         }
1581
1582         ret = qemu_write_full(fd, buf, size);
1583
1584 done:
1585         return ret;
1586 }
1587
1588 static int usb_mtp_update_object(MTPObject *parent, char *name)
1589 {
1590     int ret = 0;
1591
1592     MTPObject *o =
1593         usb_mtp_object_lookup_name(parent, name, strlen(name));
1594
1595     if (o) {
1596         ret = lstat(o->path, &o->stat);
1597     }
1598
1599     return ret;
1600 }
1601
1602 static void usb_mtp_write_data(MTPState *s, uint32_t handle)
1603 {
1604     MTPData *d = s->data_out;
1605     MTPObject *parent =
1606         usb_mtp_object_lookup(s, s->dataset.parent_handle);
1607     char *path = NULL;
1608     uint64_t rc;
1609     mode_t mask = 0644;
1610     int ret = 0;
1611
1612     assert(d != NULL);
1613
1614     switch (d->write_status) {
1615     case WRITE_START:
1616         if (!parent || !s->write_pending) {
1617             usb_mtp_queue_result(s, RES_INVALID_OBJECTINFO, d->trans,
1618                 0, 0, 0, 0);
1619             return;
1620         }
1621
1622         if (s->dataset.filename) {
1623             path = g_strdup_printf("%s/%s", parent->path, s->dataset.filename);
1624             if (s->dataset.format == FMT_ASSOCIATION) {
1625                 ret = mkdir(path, mask);
1626                 if (!ret) {
1627                     usb_mtp_queue_result(s, RES_OK, d->trans, 3,
1628                                          QEMU_STORAGE_ID,
1629                                          s->dataset.parent_handle,
1630                                          handle);
1631                     goto close;
1632                 }
1633                 goto done;
1634             }
1635
1636             d->fd = open(path, O_CREAT | O_WRONLY |
1637                          O_CLOEXEC | O_NOFOLLOW, mask);
1638             if (d->fd == -1) {
1639                 ret = 1;
1640                 goto done;
1641             }
1642
1643             /* Return success if initiator sent 0 sized data */
1644             if (!s->dataset.size) {
1645                 goto done;
1646             }
1647             if (d->length != MTP_WRITE_BUF_SZ && !d->pending) {
1648                 d->write_status = WRITE_END;
1649             }
1650         }
1651         /* fall through */
1652     case WRITE_CONTINUE:
1653     case WRITE_END:
1654         rc = write_retry(d->fd, d->data, d->data_offset,
1655                          d->offset - d->data_offset);
1656         if (rc != d->data_offset) {
1657             ret = 1;
1658             goto done;
1659         }
1660         if (d->write_status != WRITE_END) {
1661             g_free(path);
1662             return;
1663         } else {
1664             /*
1665              * Return an incomplete transfer if file size doesn't match
1666              * for < 4G file or if lstat fails which will result in an incorrect
1667              * file size
1668              */
1669             if ((s->dataset.size != 0xFFFFFFFF &&
1670                  d->offset != s->dataset.size) ||
1671                 usb_mtp_update_object(parent, s->dataset.filename)) {
1672                 usb_mtp_queue_result(s, RES_INCOMPLETE_TRANSFER, d->trans,
1673                                      0, 0, 0, 0);
1674                 goto close;
1675             }
1676         }
1677     }
1678
1679 done:
1680     if (ret) {
1681         usb_mtp_queue_result(s, RES_STORE_FULL, d->trans,
1682                              0, 0, 0, 0);
1683     } else {
1684         usb_mtp_queue_result(s, RES_OK, d->trans,
1685                              0, 0, 0, 0);
1686     }
1687 close:
1688     /*
1689      * The write dataset is kept around and freed only
1690      * on success or if another write request comes in
1691      */
1692     if (d->fd != -1) {
1693         close(d->fd);
1694         d->fd = -1;
1695     }
1696     g_free(s->dataset.filename);
1697     s->dataset.size = 0;
1698     g_free(path);
1699     s->write_pending = false;
1700 }
1701
1702 static void usb_mtp_write_metadata(MTPState *s, uint64_t dlen)
1703 {
1704     MTPData *d = s->data_out;
1705     ObjectInfo *dataset = (ObjectInfo *)d->data;
1706     char *filename;
1707     MTPObject *o;
1708     MTPObject *p = usb_mtp_object_lookup(s, s->dataset.parent_handle);
1709     uint32_t next_handle = s->next_handle;
1710     size_t filename_chars = dlen - offsetof(ObjectInfo, filename);
1711
1712     /*
1713      * filename is utf-16. We're intentionally doing
1714      * integer division to truncate if malicious guest
1715      * sent an odd number of bytes.
1716      */
1717     filename_chars /= 2;
1718
1719     assert(!s->write_pending);
1720     assert(p != NULL);
1721
1722     filename = utf16_to_str(MIN(dataset->length, filename_chars),
1723                             dataset->filename);
1724
1725     if (strchr(filename, '/')) {
1726         usb_mtp_queue_result(s, RES_PARAMETER_NOT_SUPPORTED, d->trans,
1727                              0, 0, 0, 0);
1728         g_free(filename);
1729         return;
1730     }
1731
1732     o = usb_mtp_object_lookup_name(p, filename, -1);
1733     if (o != NULL) {
1734         next_handle = o->handle;
1735     }
1736
1737     s->dataset.filename = filename;
1738     s->dataset.format = dataset->format;
1739     s->dataset.size = dataset->size;
1740     s->write_pending = true;
1741
1742     if (s->dataset.format == FMT_ASSOCIATION) {
1743         usb_mtp_write_data(s, next_handle);
1744     } else {
1745         usb_mtp_queue_result(s, RES_OK, d->trans, 3, QEMU_STORAGE_ID,
1746                              s->dataset.parent_handle, next_handle);
1747     }
1748 }
1749
1750 static void usb_mtp_get_data(MTPState *s, mtp_container *container,
1751                              USBPacket *p)
1752 {
1753     MTPData *d = s->data_out;
1754     uint64_t dlen;
1755     uint32_t data_len = p->iov.size;
1756     uint64_t total_len;
1757
1758     if (!d) {
1759             usb_mtp_queue_result(s, RES_INVALID_OBJECTINFO, 0,
1760                                  0, 0, 0, 0);
1761             return;
1762     }
1763     if (d->first) {
1764         /* Total length of incoming data */
1765         total_len = cpu_to_le32(container->length) - sizeof(mtp_container);
1766         /* Length of data in this packet */
1767         data_len -= sizeof(mtp_container);
1768         if (total_len < MTP_WRITE_BUF_SZ) {
1769                 usb_mtp_realloc(d, total_len);
1770                 d->length += total_len;
1771         } else {
1772                 usb_mtp_realloc(d, MTP_WRITE_BUF_SZ - sizeof(mtp_container));
1773                 d->length += MTP_WRITE_BUF_SZ - sizeof(mtp_container);
1774         }
1775         d->offset = 0;
1776         d->first = false;
1777         d->pending = false;
1778         d->data_offset = 0;
1779         d->write_status = WRITE_START;
1780     }
1781
1782     if (d->pending) {
1783         memset(d->data, 0, d->length);
1784         if (d->length != MTP_WRITE_BUF_SZ) {
1785             usb_mtp_realloc(d, MTP_WRITE_BUF_SZ - d->length);
1786             d->length += (MTP_WRITE_BUF_SZ - d->length);
1787         }
1788         d->pending = false;
1789         d->write_status = WRITE_CONTINUE;
1790         d->data_offset = 0;
1791     }
1792
1793     if (d->length - d->data_offset > data_len) {
1794         dlen = data_len;
1795     } else {
1796         dlen = d->length - d->data_offset;
1797     }
1798
1799     switch (d->code) {
1800     case CMD_SEND_OBJECT_INFO:
1801         usb_packet_copy(p, d->data + d->data_offset, dlen);
1802         d->offset += dlen;
1803         d->data_offset += dlen;
1804         if (d->data_offset == d->length) {
1805             /* The operation might have already failed */
1806             if (!s->result) {
1807                 usb_mtp_write_metadata(s, dlen);
1808             }
1809             usb_mtp_data_free(s->data_out);
1810             s->data_out = NULL;
1811             return;
1812         }
1813         break;
1814     case CMD_SEND_OBJECT:
1815         usb_packet_copy(p, d->data + d->data_offset, dlen);
1816         d->offset += dlen;
1817         d->data_offset += dlen;
1818         if ((p->iov.size % 64) || !p->iov.size) {
1819             assert((s->dataset.size == 0xFFFFFFFF) ||
1820                    (s->dataset.size == d->offset));
1821
1822             if (d->length == MTP_WRITE_BUF_SZ) {
1823                 d->write_status = WRITE_END;
1824             } else {
1825                 d->write_status = WRITE_START;
1826             }
1827             usb_mtp_write_data(s, 0);
1828             usb_mtp_data_free(s->data_out);
1829             s->data_out = NULL;
1830             return;
1831         }
1832         if (d->data_offset == d->length) {
1833             d->pending = true;
1834             usb_mtp_write_data(s, 0);
1835         }
1836         break;
1837     default:
1838         p->status = USB_RET_STALL;
1839         return;
1840     }
1841 }
1842
1843 static void usb_mtp_handle_data(USBDevice *dev, USBPacket *p)
1844 {
1845     MTPState *s = USB_MTP(dev);
1846     MTPControl cmd;
1847     mtp_container container;
1848     uint32_t params[5];
1849     uint16_t container_type;
1850     int i, rc;
1851
1852     switch (p->ep->nr) {
1853     case EP_DATA_IN:
1854         if (s->data_out != NULL) {
1855             /* guest bug */
1856             trace_usb_mtp_stall(s->dev.addr, "awaiting data-out");
1857             p->status = USB_RET_STALL;
1858             return;
1859         }
1860         if (p->iov.size < sizeof(container)) {
1861             trace_usb_mtp_stall(s->dev.addr, "packet too small");
1862             p->status = USB_RET_STALL;
1863             return;
1864         }
1865         if (s->data_in !=  NULL) {
1866             MTPData *d = s->data_in;
1867             uint64_t dlen = d->length - d->offset;
1868             if (d->first) {
1869                 trace_usb_mtp_data_in(s->dev.addr, d->trans, d->length);
1870                 if (d->length + sizeof(container) > 0xFFFFFFFF) {
1871                     container.length = cpu_to_le32(0xFFFFFFFF);
1872                 } else {
1873                     container.length =
1874                         cpu_to_le32(d->length + sizeof(container));
1875                 }
1876                 container.type   = cpu_to_le16(TYPE_DATA);
1877                 container.code   = cpu_to_le16(d->code);
1878                 container.trans  = cpu_to_le32(d->trans);
1879                 usb_packet_copy(p, &container, sizeof(container));
1880                 d->first = false;
1881                 if (dlen > p->iov.size - sizeof(container)) {
1882                     dlen = p->iov.size - sizeof(container);
1883                 }
1884             } else {
1885                 if (dlen > p->iov.size) {
1886                     dlen = p->iov.size;
1887                 }
1888             }
1889             if (d->fd == -1) {
1890                 usb_packet_copy(p, d->data + d->offset, dlen);
1891             } else {
1892                 if (d->alloc < p->iov.size) {
1893                     d->alloc = p->iov.size;
1894                     d->data = g_realloc(d->data, d->alloc);
1895                 }
1896                 rc = read(d->fd, d->data, dlen);
1897                 if (rc != dlen) {
1898                     memset(d->data, 0, dlen);
1899                     s->result->code = RES_INCOMPLETE_TRANSFER;
1900                 }
1901                 usb_packet_copy(p, d->data, dlen);
1902             }
1903             d->offset += dlen;
1904             if (d->offset == d->length) {
1905                 usb_mtp_data_free(s->data_in);
1906                 s->data_in = NULL;
1907             }
1908         } else if (s->result != NULL) {
1909             MTPControl *r = s->result;
1910             int length = sizeof(container) + r->argc * sizeof(uint32_t);
1911             if (r->code == RES_OK) {
1912                 trace_usb_mtp_success(s->dev.addr, r->trans,
1913                                       (r->argc > 0) ? r->argv[0] : 0,
1914                                       (r->argc > 1) ? r->argv[1] : 0);
1915             } else {
1916                 trace_usb_mtp_error(s->dev.addr, r->code, r->trans,
1917                                     (r->argc > 0) ? r->argv[0] : 0,
1918                                     (r->argc > 1) ? r->argv[1] : 0);
1919             }
1920             container.length = cpu_to_le32(length);
1921             container.type   = cpu_to_le16(TYPE_RESPONSE);
1922             container.code   = cpu_to_le16(r->code);
1923             container.trans  = cpu_to_le32(r->trans);
1924             for (i = 0; i < r->argc; i++) {
1925                 params[i] = cpu_to_le32(r->argv[i]);
1926             }
1927             usb_packet_copy(p, &container, sizeof(container));
1928             usb_packet_copy(p, &params, length - sizeof(container));
1929             g_free(s->result);
1930             s->result = NULL;
1931         }
1932         break;
1933     case EP_DATA_OUT:
1934         if (p->iov.size < sizeof(container)) {
1935             trace_usb_mtp_stall(s->dev.addr, "packet too small");
1936             p->status = USB_RET_STALL;
1937             return;
1938         }
1939         if ((s->data_out != NULL) && !s->data_out->first) {
1940             container_type = TYPE_DATA;
1941         } else {
1942             usb_packet_copy(p, &container, sizeof(container));
1943             container_type = le16_to_cpu(container.type);
1944         }
1945         switch (container_type) {
1946         case TYPE_COMMAND:
1947             if (s->data_in || s->data_out || s->result) {
1948                 trace_usb_mtp_stall(s->dev.addr, "transaction inflight");
1949                 p->status = USB_RET_STALL;
1950                 return;
1951             }
1952             cmd.code = le16_to_cpu(container.code);
1953             cmd.argc = (le32_to_cpu(container.length) - sizeof(container))
1954                 / sizeof(uint32_t);
1955             cmd.trans = le32_to_cpu(container.trans);
1956             if (cmd.argc > ARRAY_SIZE(cmd.argv)) {
1957                 cmd.argc = ARRAY_SIZE(cmd.argv);
1958             }
1959             if (p->iov.size < sizeof(container) + cmd.argc * sizeof(uint32_t)) {
1960                 trace_usb_mtp_stall(s->dev.addr, "packet too small");
1961                 p->status = USB_RET_STALL;
1962                 return;
1963             }
1964             usb_packet_copy(p, &params, cmd.argc * sizeof(uint32_t));
1965             for (i = 0; i < cmd.argc; i++) {
1966                 cmd.argv[i] = le32_to_cpu(params[i]);
1967             }
1968             trace_usb_mtp_command(s->dev.addr, cmd.code, cmd.trans,
1969                                   (cmd.argc > 0) ? cmd.argv[0] : 0,
1970                                   (cmd.argc > 1) ? cmd.argv[1] : 0,
1971                                   (cmd.argc > 2) ? cmd.argv[2] : 0,
1972                                   (cmd.argc > 3) ? cmd.argv[3] : 0,
1973                                   (cmd.argc > 4) ? cmd.argv[4] : 0);
1974             usb_mtp_command(s, &cmd);
1975             break;
1976         case TYPE_DATA:
1977             /* One of the previous transfers has already errored but the
1978              * responder is still sending data associated with it
1979              */
1980             if (s->result != NULL) {
1981                 return;
1982             }
1983             usb_mtp_get_data(s, &container, p);
1984             break;
1985         default:
1986             /* not needed as long as the mtp device is read-only */
1987             p->status = USB_RET_STALL;
1988             return;
1989         }
1990         break;
1991     case EP_EVENT:
1992         if (!QTAILQ_EMPTY(&s->events)) {
1993             struct MTPMonEntry *e = QTAILQ_LAST(&s->events);
1994             uint32_t handle;
1995             int len = sizeof(container) + sizeof(uint32_t);
1996
1997             if (p->iov.size < len) {
1998                 trace_usb_mtp_stall(s->dev.addr,
1999                                     "packet too small to send event");
2000                 p->status = USB_RET_STALL;
2001                 return;
2002             }
2003
2004             QTAILQ_REMOVE(&s->events, e, next);
2005             container.length = cpu_to_le32(len);
2006             container.type = cpu_to_le32(TYPE_EVENT);
2007             container.code = cpu_to_le16(e->event);
2008             container.trans = 0; /* no trans specific events */
2009             handle = cpu_to_le32(e->handle);
2010             usb_packet_copy(p, &container, sizeof(container));
2011             usb_packet_copy(p, &handle, sizeof(uint32_t));
2012             g_free(e);
2013             return;
2014         }
2015         p->status = USB_RET_NAK;
2016         return;
2017     default:
2018         trace_usb_mtp_stall(s->dev.addr, "invalid endpoint");
2019         p->status = USB_RET_STALL;
2020         return;
2021     }
2022
2023     if (p->actual_length == 0) {
2024         trace_usb_mtp_nak(s->dev.addr, p->ep->nr);
2025         p->status = USB_RET_NAK;
2026         return;
2027     } else {
2028         trace_usb_mtp_xfer(s->dev.addr, p->ep->nr, p->actual_length,
2029                            p->iov.size);
2030         return;
2031     }
2032 }
2033
2034 static void usb_mtp_realize(USBDevice *dev, Error **errp)
2035 {
2036     MTPState *s = USB_MTP(dev);
2037
2038     usb_desc_create_serial(dev);
2039     usb_desc_init(dev);
2040     QTAILQ_INIT(&s->objects);
2041     if (s->desc == NULL) {
2042         if (s->root == NULL) {
2043             error_setg(errp, "usb-mtp: rootdir property must be configured");
2044             return;
2045         }
2046         s->desc = strrchr(s->root, '/');
2047         if (s->desc && s->desc[0]) {
2048             s->desc = g_strdup(s->desc + 1);
2049         } else {
2050             s->desc = g_strdup("none");
2051         }
2052     }
2053     /* Mark store as RW */
2054     if (!s->readonly) {
2055         s->flags |= (1 << MTP_FLAG_WRITABLE);
2056     }
2057
2058 }
2059
2060 static const VMStateDescription vmstate_usb_mtp = {
2061     .name = "usb-mtp",
2062     .unmigratable = 1,
2063     .version_id = 1,
2064     .minimum_version_id = 1,
2065     .fields = (VMStateField[]) {
2066         VMSTATE_USB_DEVICE(dev, MTPState),
2067         VMSTATE_END_OF_LIST()
2068     }
2069 };
2070
2071 static Property mtp_properties[] = {
2072     DEFINE_PROP_STRING("rootdir", MTPState, root),
2073     DEFINE_PROP_STRING("desc", MTPState, desc),
2074     DEFINE_PROP_BOOL("readonly", MTPState, readonly, true),
2075     DEFINE_PROP_END_OF_LIST(),
2076 };
2077
2078 static void usb_mtp_class_initfn(ObjectClass *klass, void *data)
2079 {
2080     DeviceClass *dc = DEVICE_CLASS(klass);
2081     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
2082
2083     uc->realize        = usb_mtp_realize;
2084     uc->product_desc   = "QEMU USB MTP";
2085     uc->usb_desc       = &desc;
2086     uc->cancel_packet  = usb_mtp_cancel_packet;
2087     uc->handle_attach  = usb_desc_attach;
2088     uc->handle_reset   = usb_mtp_handle_reset;
2089     uc->handle_control = usb_mtp_handle_control;
2090     uc->handle_data    = usb_mtp_handle_data;
2091     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
2092     dc->desc = "USB Media Transfer Protocol device";
2093     dc->fw_name = "mtp";
2094     dc->vmsd = &vmstate_usb_mtp;
2095     dc->props = mtp_properties;
2096 }
2097
2098 static TypeInfo mtp_info = {
2099     .name          = TYPE_USB_MTP,
2100     .parent        = TYPE_USB_DEVICE,
2101     .instance_size = sizeof(MTPState),
2102     .class_init    = usb_mtp_class_initfn,
2103 };
2104
2105 static void usb_mtp_register_types(void)
2106 {
2107     type_register_static(&mtp_info);
2108 }
2109
2110 type_init(usb_mtp_register_types)