path: root/hw/usb-ccid.c

/*
 * CCID Device emulation
 *
 * Copyright (c) 2006 CodeSourcery.
 * Copyright (c) 2008 Samuel Thibault <samuel.thibault@ens-lyon.org>
 * Copyright (c) 2010 Red Hat.
 * Written by Paul Brook, reused for FTDI by Samuel Thibault,
 * reused for CCID by Alon Levy.
 *
 * This code is licenced under the LGPL.
 */

/* TODO
 *
 * Discard additional answers
 * Don't change answer while sending a multiple packet BULK_IN (answer_len > single_packet_len == 64)
 *
 */

#include "qemu-common.h"
#include "qemu-error.h"
#include "usb.h"
#include "qemu-char.h"

#include "scard_common.h"

#define DEBUG_CCID

#ifdef DEBUG_CCID
#define DPRINTF(fmt, ...) \
do { printf("usb-ccid: " fmt , ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) do {} while(0)
#endif

#define RECV_BUF 384

#define DeviceOutVendor        ((USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)
#define DeviceInVendor         ((USB_DIR_IN |USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)

#define CCID_CONTROL_ABORT                  0x1
#define CCID_CONTROL_GET_CLOCK_FREQUENCIES  0x2
#define CCID_CONTROL_GET_DATA_RATES         0x3

#define IMPERSONATE_ATHENA
#ifdef IMPERSONATE_ATHENA
#define CCID_PRODUCT_DESCRIPTION "ASEDrive CCID"
#define CCID_VENDOR_DESCRIPTION "QEMU " QEMU_VERSION
#define CCID_INTERFACE_NAME "CCID Interface"
#define CCID_SERIAL_NUMBER_STRING "ASE016"
#else
#define CCID_PRODUCT_DESCRIPTION "QEMU USB CCID"
#define CCID_VENDOR_DESCRIPTION "QEMU " QEMU_VERSION
#define CCID_INTERFACE_NAME "CCID Interface"
#define CCID_SERIAL_NUMBER_STRING "1"
#endif

// BULK_OUT messages from PC to Reader
// Defined in CCID Rev 1.1 6.1 (page 26)
#define CCID_MESSAGE_TYPE_PC_to_RDR_IccPowerOn              0x62
#define CCID_MESSAGE_TYPE_PC_to_RDR_IccPowerOff             0x63
#define CCID_MESSAGE_TYPE_PC_to_RDR_GetSlotStatus           0x65
#define CCID_MESSAGE_TYPE_PC_to_RDR_XfrBlock                0x6f
#define CCID_MESSAGE_TYPE_PC_to_RDR_GetParameters           0x6c
#define CCID_MESSAGE_TYPE_PC_to_RDR_ResetParameters         0x6d
#define CCID_MESSAGE_TYPE_PC_to_RDR_SetParameters           0x61
#define CCID_MESSAGE_TYPE_PC_to_RDR_Escape                  0x6b
#define CCID_MESSAGE_TYPE_PC_to_RDR_IccClock                0x6e
#define CCID_MESSAGE_TYPE_PC_to_RDR_T0APDU                  0x6a
#define CCID_MESSAGE_TYPE_PC_to_RDR_Secure                  0x69
#define CCID_MESSAGE_TYPE_PC_to_RDR_Mechanical              0x71
#define CCID_MESSAGE_TYPE_PC_to_RDR_Abort                   0x72
#define CCID_MESSAGE_TYPE_PC_to_RDR_SetDataRateAndClockFrequency 0x73

// BULK_IN messages from Reader to PC
// Defined in CCID Rev 1.1 6.2 (page 48)
#define CCID_MESSAGE_TYPE_RDR_to_PC_DataBlock               0x80
#define CCID_MESSAGE_TYPE_RDR_to_PC_SlotStatus              0x81
#define CCID_MESSAGE_TYPE_RDR_to_PC_Parameters              0x82
#define CCID_MESSAGE_TYPE_RDR_to_PC_Escape                  0x83
#define CCID_MESSAGE_TYPE_RDR_to_PC_DataRateAndClockFrequency 0x84

// INTERRUPT_IN messages from Reader to PC
// Defined in CCID Rev 1.1 6.3 (page 56)
#define CCID_MESSAGE_TYPE_RDR_to_PC_NotifySlotChange        0x50
#define CCID_MESSAGE_TYPE_RDR_to_PC_HardwareError           0x51

// Endpoints for CCID - addresses are up to us to decide.
// To support slot insertion and removal we must have an interrupt in ep
// in addition we need a bulk in and bulk out ep
// 5.2, page 20
#define CCID_INT_IN_EP      1
#define CCID_BULK_IN_EP     2
#define CCID_BULK_OUT_EP    3

// bmSlotICCState masks
#define SLOT_0_STATE_MASK    1
#define SLOT_0_CHANGED_MASK  2

// Status codes that go in bStatus (see 6.2.6)
enum {
    ICC_STATUS_PRESENT_ACTIVE = 0,
    ICC_STATUS_PRESENT_INACTIVE,
    ICC_STATUS_NOT_PRESENT
};

enum {
    COMMAND_STATUS_NO_ERROR = 0,
    COMMAND_STATUS_FAILED,
    COMMAND_STATUS_TIME_EXTENSION_REQUIRED
};

// Error codes that go in bError (see 6.2.6)
// There is no such thing as ERROR_NONE, just easy to
// spot places where the author thought there is no error code
// to transmit.
#define ERROR_NONE 0
enum {
    ERROR_CMD_ABORTED = -1,
    ERROR_ICC_MUTE = -2,
    ERROR_XFR_PARITY_ERROR = -3,
    ERROR_XFR_OVERRUN = -4,
    ERROR_HW_ERROR = -5,
};

// 6.2.6 RDR_to_PC_SlotStatus definitions
enum {
    CLOCK_STATUS_RUNNING=0,
 // 0 - Clock Running, 1 - Clock stopped in State L, 2 - H, 3 - unkonwn state. rest are RFU
};

typedef struct __attribute__ ((__packed__)) {
    uint8_t     bMessageType;
    uint32_t    dwLength;
    uint8_t     bSlot;
    uint8_t     bSeq;
} CCID_Header;

typedef struct __attribute__ ((__packed__)) {
    CCID_Header hdr;
    uint8_t     bStatus;        // Only used in BULK_IN
    uint8_t     bError;         // Only used in BULK_IN
} CCID_BULK_IN;

typedef struct __attribute__ ((__packed__)) {
    CCID_BULK_IN b;
    uint8_t     bClockStatus;
} CCID_SlotStatus;

typedef struct __attribute__ ((__packed__)) {
    CCID_BULK_IN b;
    uint8_t     bProtocolNum;
    uint8_t     abProtocolDataStructure[0];
} CCID_Parameter;

typedef struct __attribute__ ((__packed__)) {
    CCID_BULK_IN b;
    uint8_t      bChainParameter;
    uint8_t      abData[0];
} CCID_DataBlock;

// 6.1.4 PC_to_RDR_XfrBlock
typedef struct __attribute__ ((__packed__)) {
    CCID_Header  hdr;
    uint8_t      bBWI; // Block Waiting Timeout
    uint16_t     wLevelParameter;
    uint8_t      abData[0];
} CCID_XferBlock;

typedef struct __attribute__ ((__packed__)) {
    CCID_Header hdr;
    uint8_t     bPowerSelect;
    uint16_t    abRFU;
} CCID_IccPowerOn;

typedef struct __attribute__ ((__packed__)) {
    CCID_Header hdr;
    uint8_t     bProtocolNum;
    uint8_t    abProtocolDataStructure[0];
} CCID_SetParameter;

typedef struct {
    uint8_t     bMessageType; // CCID_MESSAGE_TYPE_RDR_to_PC_NotifySlotChange
    uint8_t     bmSlotICCState;
} CCID_Notify_Slot_Change;

#define MAX_ATR_SIZE 40
#define MAX_PROTOCOL_SIZE 7
typedef struct {
    USBDevice dev;
    CharDriverState *cs;
    uint8_t  atr[MAX_ATR_SIZE];
    uint8_t  atr_length;
    uint8_t  recv_buf[RECV_BUF];
    uint16_t recv_ptr;
    uint16_t recv_used;
    uint8_t  bmSlotICCState;
    bool     notify_slot_change;
    bool     waiting_for_answer;
    uint64_t last_answer_error;
    uint8_t  answer_slot;    // used for DataBlock response to XferBlock
    uint8_t  answer_seq;     // ditto
    uint8_t  bError;
    uint8_t  bmCommandStatus;
    uint8_t  bProtocolNum;
    uint8_t  abProtocolDataStructure[MAX_PROTOCOL_SIZE];
    uint32_t ulProtocolDataStructureSize;
} USBCCIDState;

/* Slot specific variables. We emulate a single slot card reader.
 */

uint8_t DEFAULT_ATR[] = {
// From some example somewhere
// 0x3B, 0xB0, 0x18, 0x00, 0xD1, 0x81, 0x05, 0xB1, 0x40, 0x38, 0x1F, 0x03, 0x28

// From an Athena smart card
 0x3B, 0xD5, 0x18, 0xFF, 0x80, 0x91, 0xFE, 0x1F, 0xC3, 0x80, 0x73, 0xC8, 0x21, 0x13, 0x08

}; // maximum size of ATR - from 7816-3


/* CCID Spec chapter 4: CCID uses a standard device descriptor per Chapter 9,
 * "USB Device Framework", section 9.6.1, in the Universal Serial Bus Specification.
 *
 * This device implemented based on the spec and with an Athena Smart Card Reader
 * as reference:
 *   0dc3:1004 Athena Smartcard Solutions, Inc.
 */

static const uint8_t qemu_ccid_dev_descriptor[] = {
        0x12,       /*  u8 bLength; */
        USB_DT_DEVICE, /*  u8 bDescriptorType; Device */
        0x10, 0x01, /*  u16 bcdUSB; v1.1 */

        0x00,       /*  u8  bDeviceClass; */
        0x00,       /*  u8  bDeviceSubClass; */
        0x00,       /*  u8  bDeviceProtocol; [ low/full speeds only ] */
        0x40,       /*  u8  bMaxPacketSize0; 8 Bytes (valid: 8,16,32,64) */

        /* Vendor and product id are arbitrary.  */
        0xc3, 0x0d, /*  u16 idVendor; Taken from usb-serial,
                     *  using Athena - 0dc3 */
        0x04, 0x10, /*  u16 idProduct; using Athena Smartcard Reader II 1004 */
        0x02, 0x05, /*  u16 bcdDevice; version.
                     *  update whenever a change is done. */
        0x01,       /*  u8  iManufacturer; */
        0x02,       /*  u8  iProduct; */
        0x03,       /*  u8  iSerialNumber; */
        0x01,       /*  u8  bNumConfigurations; */
};

static const uint8_t qemu_ccid_config_descriptor[] = {

        /* one configuration */
        0x09,       /*  u8  bLength; */
        USB_DT_CONFIG, /*  u8  bDescriptorType; Configuration */
        0x5d, 0x00, /*  u16 wTotalLength; 9+9+54+7+7+7 */
        0x01,       /*  u8  bNumInterfaces; (1) */
        0x01,       /*  u8  bConfigurationValue; */
        0x00,       /*  u8  iConfiguration; */
        0x80,       /*  u8  bmAttributes;
                                 Bit 7: must be set,
                                     6: Self-powered,
                                     5: Remote wakeup,
                                     4..0: resvd */
        100/2,      /*  u8  MaxPower; 50 == 100mA */

        /* one interface */
        0x09,       /*  u8  if_bLength; */
        USB_DT_INTERFACE, /*  u8  if_bDescriptorType; Interface */
        0x00,       /*  u8  if_bInterfaceNumber; */
        0x00,       /*  u8  if_bAlternateSetting; */
        0x03,       /*  u8  if_bNumEndpoints; */
        0x0b,       /*  u8  if_bInterfaceClass; Smart Card Device Class */
        0x00,       /*  u8  if_bInterfaceSubClass; Subclass code */
        0x00,       /*  u8  if_bInterfaceProtocol; Protocol code */
        0x04,       /*  u8  if_iInterface; Index of string descriptor */

        /* Smart Card Device Class Descriptor */
        0x36,       /*  u8  bLength; */
        0x21,       /*  u8  bDescriptorType; Functional */
        0x10, 0x01, /*  u16 bcdCCID; CCID Specification Release Number. */
        0x00,       /*  u8  bMaxSlotIndex; The index of the highest available
                        slot on this device. All slots are consecutive starting
                        at 00h. */
        0x07,       /*  u8  bVoltageSupport; 01h - 5.0v, 02h - 3.0, 03 - 1.8 */

        0x03, 0x00, /*  u32 dwProtocols; RRRR PPPP. RRRR = 0000h.*/
        0x00, 0x00, /*  PPPP: 0001h = Protocol T=0, 0002h = Protocol T=1 */
                    /*  u32 dwDefaultClock; in kHZ (0x1000 is 4 MHz) */
        0x00, 0x10, 0x00, 0x00,
                    /*  u32 dwMaximumClock; */
        0x00, 0x10, 0x00, 0x00,
        0x00,       /*  u8 bNumClockSupported; 0 means just the default and max. */
                    /*  u32 dwDataRate ;bps. 9600 == 00002580h, 115200 = 0001C200 */
        0x00, 0xC2, 0x01, 0x00,
                    /*  u32 dwMaxDataRate ; 9600 bps == 00002580h */
        0x00, 0xC2, 0x01, 0x00,
        0x00,       /*  u8  bNumDataRatesSupported; 00 means all rates between
                     *      default and max */
                    /*  u32 dwMaxIFSD; maximum IFSD supported by CCID for protocol
                     *      T=1 TODO (copied from Athena) */
        0xfc, 0x00, 0x00, 0x00,
                    /*  u32 dwSyncProtocols; 1 - 2-wire, 2 - 3-wire, 4 - I2C */
        0x00, 0x00, 0x00, 0x00,
                    /*  u32 dwMechanical;  0 - no special characteristics. */
        0x00, 0x00, 0x00, 0x00,
                    /*  u32 dwFeatures;
                     *  0 - No special characteristics
                     *  + 2 Automatic parameter configuration based on ATR data
                     *  4 Automatic activation of ICC on insertinc
                     *  8 Automatic ICC voltage selection
                     *  + 10 Automatic ICC clock frequency change
                     *  + 20 Automatic baud rate change
                     *  40 Automatic parameters negotiation made by the CCID
                     *  80 automatic PPS made by the CCID
                     *  100 CCID can set ICC in clock stop mode
                     *  200 NAD value other then 00 accepted (T=1 protocol)
                     *  400 Automatic IFSD exchange as first exchange (T=1)
                     *  One of the following only:
                     *  10000 TPDU level exchanges with CCID
                     *  20000 Short APDU level exchange with CCID
                     *  + 40000 Short and Extended APDU level exchange with CCID
                     *
                     *  100000 USB Wake up signaling supported on card insertion
                     *  and removal. Must set bit 5 in bmAttributes in Configuration
                     *  descriptor if 100000 is set.*/
        0x32, 0x00, 0x04, 0x00,
                    /*  u32 dwMaxCCIDMessageLength; For extended APDU in [261 + 10
                     *  , 65544 + 10]. Otherwise the minimum is wMaxPacketSize of
                     *  the Bulk-OUT endpoint */
        0x12, 0x00, 0x01, 0x00,
        0xFF,       /*  u8  bClassGetResponse; Significant only for CCID that
                     *  offers an APDU level for exchanges. Indicates the default
                     *  class value used by the CCID when it sends a Get Response
                     *  command to perform the transportation of an APDU by T=0
                     *  protocol
                     *  FFh indicates that the CCID echos the class of the APDU.
                     */
        0xFF,       /*  u8  bClassEnvelope; EAPDU only. Envelope command for T=0 */
        0x00, 0x00, /*  u16 wLcdLayout; XXYY Number of lines (XX) and chars per
                     *  line for LCD display used for PIN entry. 0000 - no LCD */
        0x01,       /*  u8  bPINSupport; 01h PIN Verification,
                     *                   02h PIN Modification */
        0x01,       /*  u8  bMaxCCIDBusySlots; */

        /* Interrupt-IN endpoint */
        0x07,       /*  u8  ep_bLength; */
        USB_DT_ENDPOINT, /*  u8  ep_bDescriptorType; Endpoint */
        0x80 | CCID_INT_IN_EP, /*  u8  ep_bEndpointAddress; IN Endpoint 1 */
        0x03,       /*  u8  ep_bmAttributes; Interrupt */
        0x40, 0x00, /*  u16 ep_wMaxPacketSize; */
        0xff,       /*  u8  ep_bInterval; */

        /* Bulk-In endpoint */
        0x07,       /*  u8  ep_bLength; */
        USB_DT_ENDPOINT, /*  u8  ep_bDescriptorType; Endpoint */
        0x80 | CCID_BULK_IN_EP, /*  u8  ep_bEndpointAddress; IN Endpoint 2 */
        0x02,       /*  u8  ep_bmAttributes; Bulk */
        0x40, 0x00, /*  u16 ep_wMaxPacketSize; */
        0x00,       /*  u8  ep_bInterval; */

        /* Bulk-Out endpoint */
        0x07,       /*  u8  ep_bLength; */
        USB_DT_ENDPOINT, /*  u8  ep_bDescriptorType; Endpoint */
        CCID_BULK_OUT_EP,       /*  u8  ep_bEndpointAddress; OUT Endpoint 3 */
        0x02,       /*  u8  ep_bmAttributes; Bulk */
        0x40, 0x00, /*  u16 ep_wMaxPacketSize; */
        0x00,       /*  u8  ep_bInterval; */

};

static void usb_ccid_reset(USBCCIDState *s)
{
    /* TODO: Set flow control to none */
    s->recv_ptr = 0;
    s->recv_used = 0;
    /* TODO: purge in char driver */
}

static void usb_ccid_handle_reset(USBDevice *dev)
{
    USBCCIDState *s = (USBCCIDState *)dev;

    DPRINTF("Reset\n");

    usb_ccid_reset(s);
    /* TODO: Reset char device, send BREAK? */
}

static int usb_ccid_handle_control(USBDevice *dev, int request, int value,
                                  int index, int length, uint8_t *data)
{
    //USBCCIDState *s = (USBCCIDState *)dev;
    int ret = 0;

    //DPRINTF("got control %x, value %x\n",request, value);
    switch (request) {
    case DeviceRequest | USB_REQ_GET_STATUS:
        data[0] = (0 << USB_DEVICE_SELF_POWERED) |
            (dev->remote_wakeup << USB_DEVICE_REMOTE_WAKEUP);
        data[1] = 0x00;
        ret = 2;
        break;
    case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
        if (value == USB_DEVICE_REMOTE_WAKEUP) {
            dev->remote_wakeup = 0;
        } else {
            goto fail;
        }
        ret = 0;
        break;
    case DeviceOutRequest | USB_REQ_SET_FEATURE:
        if (value == USB_DEVICE_REMOTE_WAKEUP) {
            dev->remote_wakeup = 1;
        } else {
            goto fail;
        }
        ret = 0;
        break;
    case DeviceOutRequest | USB_REQ_SET_ADDRESS:
        dev->addr = value;
        ret = 0;
        break;
    case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
        switch(value >> 8) {
        case USB_DT_DEVICE:
            memcpy(data, qemu_ccid_dev_descriptor,
                   sizeof(qemu_ccid_dev_descriptor));
            ret = sizeof(qemu_ccid_dev_descriptor);
            break;
        case USB_DT_CONFIG:
            memcpy(data, qemu_ccid_config_descriptor,
                   sizeof(qemu_ccid_config_descriptor));
            ret = sizeof(qemu_ccid_config_descriptor);
            /* I got a request with size 8 - even though the
             * basic descriptor is size 9. So handle it correctly.
             * byte zero is the length*/
            /* BROKEN - TODO?
            if (length < data[0]) {
                DPRINTF("Adjusting length of descriptor to requested length\n");
                data[0] = length;
                ret = length;
            }
            */
            break;
        case USB_DT_STRING:
            switch(value & 0xff) {
            case 0:
                /* language ids */
                data[0] = 4;
                data[1] = 3;
                data[2] = 0x09;
                data[3] = 0x04;
                ret = 4;
                break;
            case 1:
                /* vendor description */
                ret = set_usb_string(data, CCID_VENDOR_DESCRIPTION);
                break;
            case 2:
                /* product description */
                ret = set_usb_string(data, CCID_PRODUCT_DESCRIPTION);
                break;
            case 3:
                /* serial number */
                ret = set_usb_string(data, CCID_SERIAL_NUMBER_STRING);
                break;
            case 4:
                /* interface name */
                ret = set_usb_string(data, CCID_INTERFACE_NAME);
                break;
            default:
                goto fail;
            }
            break;
        default:
            goto fail;
        }
        break;
    case DeviceRequest | USB_REQ_GET_CONFIGURATION:
        data[0] = 1;
        ret = 1;
        break;
    case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
        /* Only one configuration - we just ignore the request */
        ret = 0;
        break;
    case DeviceRequest | USB_REQ_GET_INTERFACE:
        data[0] = 0;
        ret = 1;
        break;
    case InterfaceOutRequest | USB_REQ_SET_INTERFACE:
        ret = 0;
        break;
    case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
        ret = 0;
        break;

        /* Class specific requests.  */
    case DeviceOutVendor | CCID_CONTROL_ABORT:
        DPRINTF("ccid_control abort\n");
        ret = USB_RET_STALL;
        break;
    case DeviceOutVendor | CCID_CONTROL_GET_CLOCK_FREQUENCIES:
        DPRINTF("ccid_control get clock frequencies\n");
        ret = USB_RET_STALL;
        break;
    case DeviceOutVendor | CCID_CONTROL_GET_DATA_RATES:
        DPRINTF("ccid_control get data rates\n");
        ret = USB_RET_STALL;
        break;
    default:
    fail:
        DPRINTF("got unsupported/bogus control %x, value %x\n", request, value);
        ret = USB_RET_STALL;
        break;
    }
    return ret;
}

static uint8_t* ccid_reserve_recv_buf(USBCCIDState* s, uint16_t len)
{
    if (len + s->recv_used > RECV_BUF) {
        printf("usb-ccid.c: %s: overflow of receive buf. bailing out.\n", __func__);
        exit(-1);
    }
    if (s->recv_used == 0) {
        s->recv_ptr = 0;
    }
    s->recv_used += len;
    return s->recv_buf + s->recv_ptr;
}

static bool usb_ccid_card_inserted(USBCCIDState *s)
{
    return s->bmSlotICCState & SLOT_0_STATE_MASK;
}

static uint8_t usb_ccid_calc_status(USBCCIDState *s)
{
    // page 55, 6.2.6, calculation of bStatus from bmICCStatus and bmCommandStatus
    return (usb_ccid_card_inserted(s) ? ICC_STATUS_PRESENT_ACTIVE : ICC_STATUS_NOT_PRESENT)
            | (s->bmCommandStatus << 6);
}

static void ccid_reset_error_status(USBCCIDState* s)
{
    s->bError = ERROR_NONE;
    s->bmCommandStatus = COMMAND_STATUS_NO_ERROR;
}

static void ccid_write_slot_status(USBCCIDState* s, CCID_Header* recv)
{
    CCID_SlotStatus *h = (CCID_SlotStatus*)ccid_reserve_recv_buf(s, 10);
    h->b.hdr.bMessageType = CCID_MESSAGE_TYPE_RDR_to_PC_SlotStatus;
    h->b.hdr.dwLength = 0;
    h->b.hdr.bSlot = recv->bSlot;
    h->b.hdr.bSeq = recv->bSeq;
    h->b.bStatus = usb_ccid_calc_status(s);
    h->b.bError = s->bError;
    h->bClockStatus = CLOCK_STATUS_RUNNING;
    ccid_reset_error_status(s);
}

static void ccid_write_parameters(USBCCIDState* s, CCID_Header* recv)
{
    CCID_Parameter *h;
    uint32_t len = s->ulProtocolDataStructureSize;

    h = (CCID_Parameter *)ccid_reserve_recv_buf(s, 10+len);
    h->b.hdr.bMessageType = CCID_MESSAGE_TYPE_RDR_to_PC_Parameters;
    h->b.hdr.dwLength = 0;
    h->b.hdr.bSlot = recv->bSlot;
    h->b.hdr.bSeq = recv->bSeq;
    h->b.bStatus = usb_ccid_calc_status(s);
    h->b.bError = s->bError;
    h->bProtocolNum = s->bProtocolNum;
    memcpy(h->abProtocolDataStructure,s->abProtocolDataStructure, len);
    ccid_reset_error_status(s);
}

static void ccid_write_data_block(
    USBCCIDState* s, uint8_t slot, uint8_t seq,
    const uint8_t* data, uint32_t len)
{
    CCID_DataBlock *p;

    if (sizeof(s->recv_buf) < sizeof(*p) + len) {
        abort();
    }
    p = (CCID_DataBlock*)ccid_reserve_recv_buf(s, sizeof(*p) + len);
    p->b.hdr.bMessageType = CCID_MESSAGE_TYPE_RDR_to_PC_DataBlock;
    p->b.hdr.dwLength = len;
    p->b.hdr.bSlot = slot;
    p->b.hdr.bSeq = seq;
    p->b.bStatus = usb_ccid_calc_status(s);
    p->b.bError = s->bError;
    memcpy(p->abData, data, len);
    ccid_reset_error_status(s);
}

static void ccid_write_data_block_answer(USBCCIDState* s, const uint8_t* data, uint32_t len)
{
    ccid_write_data_block(s, s->answer_slot, s->answer_seq, data, len);
}

static void ccid_write_data_block_atr(USBCCIDState* s, CCID_Header* recv)
{
    ccid_write_data_block(s, recv->bSlot, recv->bSeq, s->atr, s->atr_length);
}

static void ccid_set_parameters(USBCCIDState *s, CCID_Header *recv)
{
    CCID_SetParameter *ph = (CCID_SetParameter *) recv;
    uint32_t len = 0;
    if (ph->bProtocolNum == 0) {
        len = 5;
    }
    if (ph->bProtocolNum == 1) {
        len = 7;
    }
    if (len == 0) {
        s->bmCommandStatus = COMMAND_STATUS_FAILED;
        s->bError = 7; /* Protocol invalid or not supported */
        return;
    }
    s->bProtocolNum = ph->bProtocolNum;
    memcpy(s->abProtocolDataStructure, ph->abProtocolDataStructure, len);
    s->ulProtocolDataStructureSize = len;
}

/* must be 5 bytes for T=0, 7 bytes for T=1 */
static const uint8_t abDefaultProtocolDataStructure[5] =
    { 0x77, 0x00, 0x00, 0x00, 0x00 };

static void ccid_reset_parameters(USBCCIDState *s)
{
   uint32_t len = sizeof(abDefaultProtocolDataStructure);
   s->bProtocolNum = 0; /* T=0 */
   s->ulProtocolDataStructureSize = len;
   memcpy(s->abProtocolDataStructure, abDefaultProtocolDataStructure, len);
}

static void usb_ccid_on_slot_change(USBCCIDState* s, bool full)
{
    // RDR_to_PC_NotifySlotChange, 6.3.1 page 56
    uint8_t current = s->bmSlotICCState;
    if (full) {
        s->bmSlotICCState |= SLOT_0_STATE_MASK;  // Slot 0 status full
    } else {
        s->bmSlotICCState &= ~SLOT_0_STATE_MASK; // Slot 0 status empty
    }
    if (current != s->bmSlotICCState) {
        s->bmSlotICCState |= SLOT_0_CHANGED_MASK;  // Slot 0 changed
    }
    s->notify_slot_change = true;
}

static void ccid_write_data_block_error(USBCCIDState *s, uint8_t slot, uint8_t seq)
{
    ccid_write_data_block(s, slot, seq, NULL, 0);
}

static void ccid_on_apdu_from_guest(USBCCIDState *s, CCID_XferBlock* recv)
{
    static SCRMsgHeader scr_msg_header;
    if (!s->cs) {
        printf("usb-ccid: discarding apdu length %d\n", recv->hdr.dwLength);
        return;
        // XXX - dummy mode for testing, or just have the whole virtual card here.
    }
    if (!usb_ccid_card_inserted(s)) {
        printf("usb-ccid: not sending apdu to client, no card connected\n");
        ccid_write_data_block_error(s, recv->hdr.bSlot, recv->hdr.bSeq);
        return;
    }
    s->answer_slot = recv->hdr.bSlot;
    s->answer_seq = recv->hdr.bSeq;
    printf("usb-ccid: apdu_from_guest %d: len %d\n", recv->hdr.bSeq, recv->hdr.dwLength);
    scr_msg_header.type = SCard_APDU;
    scr_msg_header.nLength = recv->hdr.dwLength;
    // send request to remote card
    qemu_chr_write(s->cs, (uint8_t*)&scr_msg_header, sizeof(SCRMsgHeader));
    qemu_chr_write(s->cs, recv->abData, recv->hdr.dwLength);
    s->waiting_for_answer = true;
}

static void usb_ccid_handle_bulk_out(USBCCIDState *s, USBPacket *p)
{
    static uint8_t data[70000]; // TODO - set to correct max size of packet.
    static uint32_t len = 0;
    static CCID_Header* ccid_header = (CCID_Header*)data;

    memcpy(data + len, p->data, p->len);
    len += p->len;
    if (p->len == 64) {
        printf("usb-ccid: bulk_in: expecting more packets (%d/%d)\n",
            len, ccid_header->dwLength);
        return;
    }
    if (len < 10) {
        DPRINTF("handle_data: bad USB_TOKEN_OUT length, should be at least 10 bytes\n");
    } else {
        switch (ccid_header->bMessageType) {
            case CCID_MESSAGE_TYPE_PC_to_RDR_GetSlotStatus:
                ccid_write_slot_status(s, ccid_header);
                break;
            case CCID_MESSAGE_TYPE_PC_to_RDR_IccPowerOn:
                // We need to send an ATR back
                ccid_write_data_block_atr(s, ccid_header);
                break;
            case CCID_MESSAGE_TYPE_PC_to_RDR_XfrBlock:
                ccid_on_apdu_from_guest(s, (CCID_XferBlock*)data);
                break;
            case CCID_MESSAGE_TYPE_PC_to_RDR_SetParameters:
                s->bmCommandStatus = COMMAND_STATUS_NO_ERROR;
                ccid_set_parameters(s, ccid_header);
                ccid_write_parameters(s, ccid_header);
            break;
            case CCID_MESSAGE_TYPE_PC_to_RDR_ResetParameters:
                s->bmCommandStatus = COMMAND_STATUS_NO_ERROR;
                ccid_reset_parameters(s);
                ccid_write_parameters(s, ccid_header);
            break;
            case CCID_MESSAGE_TYPE_PC_to_RDR_GetParameters:
                s->bmCommandStatus = COMMAND_STATUS_NO_ERROR;
                ccid_write_parameters(s, ccid_header);
            break;
            default:
                DPRINTF("handle_data: ERROR: unhandled message type %Xh\n",
                    ccid_header->bMessageType);
                break;
        }
    }
    len = 0;
}

static int usb_ccid_handle_data(USBDevice *dev, USBPacket *p)
{
    USBCCIDState *s = (USBCCIDState *)dev;
    int ret = 0;
    int first_len;
    uint8_t *data = p->data;
    int len = p->len;
#ifdef DEBUG_CCID
    //int i;
#endif

    /*
    DPRINTF("handle_data: %d: got %d bytes\n", p->pid, len);
    #ifdef DEBUG_CCID
    if (len < 30) {
        DPRINTF("handle_data: ");
        for (i = 0 ; i < len ; ++i) {
            printf("%X ", data[i]);
        }
        printf("\n");
    }
    #endif
    */

    switch (p->pid) {
    case USB_TOKEN_OUT:
        usb_ccid_handle_bulk_out(s, p);
        break;

    case USB_TOKEN_IN:
        switch (p->devep & 0xf) {
            case CCID_BULK_IN_EP:
                first_len = RECV_BUF - s->recv_ptr;
                if (len > s->recv_used)
                    len = s->recv_used;
                if (!len) {
                    ret = USB_RET_NAK;
                    break;
                }
                if (first_len > len)
                    first_len = len;
                memcpy(data, s->recv_buf + s->recv_ptr, first_len);
                if (len > first_len)
                    memcpy(data + first_len, s->recv_buf, len - first_len);
                s->recv_used -= len;
                s->recv_ptr = (s->recv_ptr + len) % RECV_BUF;
                ret = len;
                /* DPRINTF("handle_data: bulk_in: sending %d bytes\n", ret);*/
                break;
            case CCID_INT_IN_EP:
                if (s->notify_slot_change) {
                    // page 56, RDR_to_PC_NotifySlotChange
                    data[0] = CCID_MESSAGE_TYPE_RDR_to_PC_NotifySlotChange;
                    data[1] = s->bmSlotICCState;
                    ret = 2;
                    s->notify_slot_change = false;
                    s->bmSlotICCState &= ~ SLOT_0_CHANGED_MASK; // next notify won't say "this changed"
                    DPRINTF("handle_data: int_in: notify_slot_change %X\n", s->bmSlotICCState);
                }
                break;
            default:
                DPRINTF("Bad endpoint\n");
                break;
        }
        break;
    default:
        DPRINTF("Bad token\n");
    //fail:
        ret = USB_RET_STALL;
        break;
    }

    return ret;
}

static void usb_ccid_handle_destroy(USBDevice *dev)
{
    USBCCIDState *s = (USBCCIDState *)dev;

    if (s->cs) {
        qemu_chr_close(s->cs);
    }
}

/* APDU chardev */

static int usb_ccid_scard_can_read(void *opaque)
{
    //USBCCIDState *s = opaque;
    return 70000; // XXX number has meaning, or just positive for yes?
}

static void usb_ccid_scard_read(void *opaque, const uint8_t *buf, int size)
{
    static uint8_t readbuf[10000];
    static uint32_t readpos = 0;
    USBCCIDState *s = opaque;
    const SCRMsgHeader* scr_msg_header = (const SCRMsgHeader*)readbuf;
    const uint8_t* data = readbuf + sizeof(SCRMsgHeader);
    uint32_t available = size + readpos;

    assert(readpos + size <= sizeof(readbuf));
    memcpy(readbuf + readpos, buf, size);
    readpos += size;

    if (available - sizeof(SCRMsgHeader) < scr_msg_header->nLength) {
        return;
    }

    readpos = 0; // ready for next message

    switch (scr_msg_header->type) {
        case SCard_ATR:
            DPRINTF("SCard_ATR %d\n", scr_msg_header->nLength);
            assert(scr_msg_header->nLength <= MAX_ATR_SIZE);
            memcpy(s->atr, data, scr_msg_header->nLength);
            s->atr_length = scr_msg_header->nLength;
            s->bmCommandStatus = COMMAND_STATUS_NO_ERROR;
            usb_ccid_on_slot_change(s, true);
            break;
        case SCard_APDU:
            if (!s->waiting_for_answer) {
                DPRINTF("SCard_APDU: ERROR: got an APDU while not waiting_for_answer\n");
                assert(s->waiting_for_answer);
            }
            s->bmCommandStatus = COMMAND_STATUS_NO_ERROR;
            DPRINTF("SCard_APDU %d (answer seq %d, slot %d)\n",
                scr_msg_header->nLength,
                s->answer_seq, s->answer_slot);
            ccid_write_data_block_answer(s, data, scr_msg_header->nLength);
            break;
        case SCard_Remove:
            DPRINTF("SCard_Remove\n");
            usb_ccid_on_slot_change(s, false);
            if (s->waiting_for_answer) {
                ccid_write_data_block_answer(s, NULL, 0);
            }
            break;
        case SCard_Error:
            // TODO - actually look at the error
            s->bmCommandStatus = COMMAND_STATUS_FAILED;
            s->last_answer_error = *(uint64_t*)data;
            DPRINTF("SCard_Error: %lX\n", s->last_answer_error);
            ccid_write_data_block_answer(s, NULL, 0);
            break;
        default:
            printf("usb-ccid: chardev: unexpected message of type %X\n",
                   scr_msg_header->type);
    };
    if (s->waiting_for_answer) {
        s->waiting_for_answer = false;
    }
}

static void usb_ccid_scard_event(void *opaque, int event)
{
    //USBCCIDState *s = opaque;
}

/* Control chardev */

static int usb_ccid_initfn(USBDevice *dev)
{
    USBCCIDState *s = DO_UPCAST(USBCCIDState, dev, dev);
    s->dev.speed = USB_SPEED_FULL;
    s->notify_slot_change = false;
    s->answer_slot = -1;
    s->answer_seq = -1;
    s->last_answer_error = 0;
    s->waiting_for_answer = false;
    ccid_reset_error_status(s);
    assert(sizeof(DEFAULT_ATR) <= MAX_ATR_SIZE);
    memcpy(s->atr, DEFAULT_ATR, sizeof(DEFAULT_ATR));
    s->atr_length = sizeof(DEFAULT_ATR);
    if (s->cs) {
        DPRINTF("initing chardev\n");
        qemu_chr_add_handlers(s->cs, usb_ccid_scard_can_read, usb_ccid_scard_read,
                              usb_ccid_scard_event, s);
    }
    ccid_reset_parameters(s);
    usb_ccid_handle_reset(dev);
    return 0;
}

static struct USBDeviceInfo ccid_info = {
    .product_desc   = "QEMU USB CCID",
    .qdev.name      = "usb-ccid",
    .qdev.size      = sizeof(USBCCIDState),
    .init           = usb_ccid_initfn,
    .handle_packet  = usb_generic_handle_packet,
    .handle_reset   = usb_ccid_handle_reset,
    .handle_control = usb_ccid_handle_control,
    .handle_data    = usb_ccid_handle_data,
    .handle_destroy = usb_ccid_handle_destroy,
    .usbdevice_name = "ccid",
    .qdev.props     = (Property[]) {
        DEFINE_PROP_CHR("chardev",     USBCCIDState, cs),
        DEFINE_PROP_END_OF_LIST(),
    },
};

static void usb_ccid_register_devices(void)
{
    usb_qdev_register(&ccid_info);
}
device_init(usb_ccid_register_devices)