[v2,2/2] usb-mtp: added object properties

Windows uses object properties to determine the size of a file, so to
add object properties, we must also add a minimum set of new commands
and object properties. Most object properties are data that we already
have, except for the unique persistant object identifier. Windows
doesn't use this property, it seems, so we can cheat a bit and just use
the object handle for it.

Signed-off-by: Isaac Lozano <109lozanoi@gmail.com>
---
 hw/usb/dev-mtp.c | 186 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 181 insertions(+), 5 deletions(-)

Isaac Lozano <109lozanoi@gmail.com> writes:

> Windows uses object properties to determine the size of a file, so to
> add object properties, we must also add a minimum set of new commands
> and object properties. Most object properties are data that we already
> have, except for the unique persistant object identifier. Windows
> doesn't use this property, it seems, so we can cheat a bit and just use
> the object handle for it.
>
> Signed-off-by: Isaac Lozano <109lozanoi@gmail.com>
> ---
>  hw/usb/dev-mtp.c | 186 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 181 insertions(+), 5 deletions(-)
>
> diff --git a/hw/usb/dev-mtp.c b/hw/usb/dev-mtp.c
> index 6f6a270..fa0c81e 100644
> --- a/hw/usb/dev-mtp.c
> +++ b/hw/usb/dev-mtp.c
> @@ -48,6 +48,9 @@ enum mtp_code {
>      CMD_GET_OBJECT_INFO            = 0x1008,
>      CMD_GET_OBJECT                 = 0x1009,
>      CMD_GET_PARTIAL_OBJECT         = 0x101b,
> +    CMD_GET_OBJECT_PROPS_SUPPORTED = 0x9801,
> +    CMD_GET_OBJECT_PROP_DESC       = 0x9802,
> +    CMD_GET_OBJECT_PROP_VALUE      = 0x9803,
>  
>      /* response codes */
>      RES_OK                         = 0x2001,
> @@ -59,10 +62,12 @@ enum mtp_code {
>      RES_INCOMPLETE_TRANSFER        = 0x2007,
>      RES_INVALID_STORAGE_ID         = 0x2008,
>      RES_INVALID_OBJECT_HANDLE      = 0x2009,
> +    RES_INVALID_OBJECT_FORMAT_CODE = 0x200b,
>      RES_SPEC_BY_FORMAT_UNSUPPORTED = 0x2014,
>      RES_INVALID_PARENT_OBJECT      = 0x201a,
>      RES_INVALID_PARAMETER          = 0x201d,
>      RES_SESSION_ALREADY_OPEN       = 0x201e,
> +    RES_INVALID_OBJECT_PROP_CODE   = 0xA801,
>  
>      /* format codes */
>      FMT_UNDEFINED_OBJECT           = 0x3000,
> @@ -72,6 +77,22 @@ enum mtp_code {
>      EVT_OBJ_ADDED                  = 0x4002,
>      EVT_OBJ_REMOVED                = 0x4003,
>      EVT_OBJ_INFO_CHANGED           = 0x4007,
> +
> +    /* object properties */
> +    PROP_STORAGE_ID                = 0xDC01,
> +    PROP_OBJECT_FORMAT             = 0xDC02,
> +    PROP_OBJECT_COMPRESSED_SIZE    = 0xDC04,
> +    PROP_PARENT_OBJECT             = 0xDC0B,
> +    PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER = 0xDC41,
> +    PROP_NAME                      = 0xDC44,
> +};
> +
> +enum mtp_data_type {
> +    DATA_TYPE_UINT16  = 0x0004,
> +    DATA_TYPE_UINT32  = 0x0006,
> +    DATA_TYPE_UINT64  = 0x0008,
> +    DATA_TYPE_UINT128 = 0x000a,
> +    DATA_TYPE_STRING  = 0xffff,
>  };
>  
>  typedef struct {
> @@ -778,6 +799,9 @@ static MTPData *usb_mtp_get_device_info(MTPState *s, MTPControl *c)
>          CMD_GET_OBJECT_INFO,
>          CMD_GET_OBJECT,
>          CMD_GET_PARTIAL_OBJECT,
> +        CMD_GET_OBJECT_PROPS_SUPPORTED,
> +        CMD_GET_OBJECT_PROP_DESC,
> +        CMD_GET_OBJECT_PROP_VALUE,
>      };
>      static const uint16_t fmt[] = {
>          FMT_UNDEFINED_OBJECT,
> @@ -886,8 +910,7 @@ static MTPData *usb_mtp_get_object_info(MTPState *s, MTPControl *c,
>  
>      if (o->stat.st_size > 0xFFFFFFFF) {
>          usb_mtp_add_u32(d, 0xFFFFFFFF);
> -    }
> -    else {
> +    } else {
>          usb_mtp_add_u32(d, o->stat.st_size);
>      }
>  
> @@ -972,6 +995,122 @@ static MTPData *usb_mtp_get_partial_object(MTPState *s, MTPControl *c,
>      return d;
>  }
>  
> +static MTPData *usb_mtp_get_object_props_supported(MTPState *s, MTPControl *c)
> +{
> +    static const uint16_t props[] = {
> +        PROP_STORAGE_ID,
> +        PROP_OBJECT_FORMAT,
> +        PROP_OBJECT_COMPRESSED_SIZE,
> +        PROP_PARENT_OBJECT,
> +        PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER,
> +        PROP_NAME,
> +    };
> +    MTPData *d = usb_mtp_data_alloc(c);
> +    usb_mtp_add_u16_array(d, ARRAY_SIZE(props), props);
> +
> +    return d;
> +}
> +
> +static MTPData *usb_mtp_get_object_prop_desc(MTPState *s, MTPControl *c)
> +{
> +    MTPData *d = usb_mtp_data_alloc(c);
> +    switch (c->argv[0]) {
> +    case PROP_STORAGE_ID:
> +        usb_mtp_add_u16(d, PROP_STORAGE_ID);
> +        usb_mtp_add_u16(d, DATA_TYPE_UINT32);
> +        usb_mtp_add_u8(d, 0x00);
> +        usb_mtp_add_u32(d, 0x00000000);
> +        usb_mtp_add_u32(d, 0x00000000);
> +        usb_mtp_add_u8(d, 0x00);
> +        break;
Stylistic:

Can rewrite all 0 valued calls to usb_mtp_add_u32(d, 0) and the like
but this is fine too :)

> +    case PROP_OBJECT_FORMAT:
> +        usb_mtp_add_u16(d, PROP_OBJECT_FORMAT);
> +        usb_mtp_add_u16(d, DATA_TYPE_UINT16);
> +        usb_mtp_add_u8(d, 0x00);
> +        usb_mtp_add_u16(d, 0x0000);
> +        usb_mtp_add_u32(d, 0x00000000);
> +        usb_mtp_add_u8(d, 0x00);
> +        break;
> +    case PROP_OBJECT_COMPRESSED_SIZE:
> +        usb_mtp_add_u16(d, PROP_OBJECT_COMPRESSED_SIZE);
> +        usb_mtp_add_u16(d, DATA_TYPE_UINT64);
> +        usb_mtp_add_u8(d, 0x00);
> +        usb_mtp_add_u64(d, 0x0000000000000000);
> +        usb_mtp_add_u32(d, 0x00000000);
> +        usb_mtp_add_u8(d, 0x00);
> +        break;
> +    case PROP_PARENT_OBJECT:
> +        usb_mtp_add_u16(d, PROP_PARENT_OBJECT);
> +        usb_mtp_add_u16(d, DATA_TYPE_UINT32);
> +        usb_mtp_add_u8(d, 0x00);
> +        usb_mtp_add_u32(d, 0x00000000);
> +        usb_mtp_add_u32(d, 0x00000000);
> +        usb_mtp_add_u8(d, 0x00);
> +        break;
> +    case PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER:
> +        usb_mtp_add_u16(d, PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER);
> +        usb_mtp_add_u16(d, DATA_TYPE_UINT128);
> +        usb_mtp_add_u8(d, 0x00);
> +        usb_mtp_add_u64(d, 0x0000000000000000);
> +        usb_mtp_add_u64(d, 0x0000000000000000);
> +        usb_mtp_add_u32(d, 0x00000000);
> +        usb_mtp_add_u8(d, 0x00);
> +        break;
> +    case PROP_NAME:
> +        usb_mtp_add_u16(d, PROP_NAME);
> +        usb_mtp_add_u16(d, DATA_TYPE_STRING);
> +        usb_mtp_add_u8(d, 0x00);
> +        usb_mtp_add_u8(d, 0x00);
> +        usb_mtp_add_u32(d, 0x00000000);
> +        usb_mtp_add_u8(d, 0x00);
> +        break;
> +    default:
> +        usb_mtp_data_free(d);
> +        return NULL;
> +    }
> +
> +    return d;
> +}
> +
> +static MTPData *usb_mtp_get_object_prop_value(MTPState *s, MTPControl *c,
> +                                              MTPObject *o)
> +{
> +    MTPData *d = usb_mtp_data_alloc(c);
> +    switch (c->argv[1]) {
> +    case PROP_STORAGE_ID:
> +        usb_mtp_add_u32(d, QEMU_STORAGE_ID);
> +        break;
> +    case PROP_OBJECT_FORMAT:
> +        usb_mtp_add_u16(d, o->format);
> +        break;
> +    case PROP_OBJECT_COMPRESSED_SIZE:
> +        usb_mtp_add_u64(d, o->stat.st_size);
> +        break;
> +    case PROP_PARENT_OBJECT:
> +        if (o->parent == NULL) {
> +            usb_mtp_add_u32(d, 0x00000000);
> +        } else {
> +            usb_mtp_add_u32(d, o->parent->handle);
> +        }
> +        break;
> +    case PROP_PERSISTENT_UNIQUE_OBJECT_IDENTIFIER:
> +        /* Should be persistant between sessions,
> +         * but using our objedt ID is "good enough"
s/objedt/object

> +         * for now */
> +        usb_mtp_add_u64(d, 0x0000000000000000);
> +        usb_mtp_add_u64(d, o->handle);

I thought we decided on the inode number ? Probably harmless but can't be handle
be different across sessions ? For example, a new file is added followed by a new
session.

Bandan

> +        break;
> +    case PROP_NAME:
> +        usb_mtp_add_str(d, o->name);
> +        break;
> +    default:
> +        usb_mtp_data_free(d);
> +        return NULL;
> +    }
> +
> +    return d;
> +}
> +
>  static void usb_mtp_command(MTPState *s, MTPControl *c)
>  {
>      MTPData *data_in = NULL;
> @@ -1119,6 +1258,43 @@ static void usb_mtp_command(MTPState *s, MTPControl *c)
>          nres = 1;
>          res0 = data_in->length;
>          break;
> +    case CMD_GET_OBJECT_PROPS_SUPPORTED:
> +        if (c->argv[0] != FMT_UNDEFINED_OBJECT &&
> +            c->argv[0] != FMT_ASSOCIATION) {
> +            usb_mtp_queue_result(s, RES_INVALID_OBJECT_FORMAT_CODE,
> +                                 c->trans, 0, 0, 0);
> +            return;
> +        }
> +        data_in = usb_mtp_get_object_props_supported(s, c);
> +        break;
> +    case CMD_GET_OBJECT_PROP_DESC:
> +        if (c->argv[1] != FMT_UNDEFINED_OBJECT &&
> +            c->argv[1] != FMT_ASSOCIATION) {
> +            usb_mtp_queue_result(s, RES_INVALID_OBJECT_FORMAT_CODE,
> +                                 c->trans, 0, 0, 0);
> +            return;
> +        }
> +        data_in = usb_mtp_get_object_prop_desc(s, c);
> +        if (data_in == NULL) {
> +            usb_mtp_queue_result(s, RES_INVALID_OBJECT_PROP_CODE,
> +                                 c->trans, 0, 0, 0);
> +            return;
> +        }
> +        break;
> +    case CMD_GET_OBJECT_PROP_VALUE:
> +        o = usb_mtp_object_lookup(s, c->argv[0]);
> +        if (o == NULL) {
> +            usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
> +                                 c->trans, 0, 0, 0);
> +            return;
> +        }
> +        data_in = usb_mtp_get_object_prop_value(s, c, o);
> +        if (data_in == NULL) {
> +            usb_mtp_queue_result(s, RES_INVALID_OBJECT_PROP_CODE,
> +                                 c->trans, 0, 0, 0);
> +            return;
> +        }
> +        break;
>      default:
>          trace_usb_mtp_op_unknown(s->dev.addr, c->code);
>          usb_mtp_queue_result(s, RES_OPERATION_NOT_SUPPORTED,
> @@ -1204,9 +1380,9 @@ static void usb_mtp_handle_data(USBDevice *dev, USBPacket *p)
>                  trace_usb_mtp_data_in(s->dev.addr, d->trans, d->length);
>                  if (d->length + sizeof(container) > 0xFFFFFFFF) {
>                      container.length = cpu_to_le32(0xFFFFFFFF);
> -                }
> -                else {
> -                    container.length = cpu_to_le32(d->length + sizeof(container));
> +                } else {
> +                    container.length = cpu_to_le32(d->length +
> +                                                   sizeof(container));
>                  }
>                  container.type   = cpu_to_le16(TYPE_DATA);
>                  container.code   = cpu_to_le16(d->code);