qemu/hw/usb/ccid-card-passthru.c

422 lines
13 KiB
C

/*
* CCID Passthru Card Device emulation
*
* Copyright (c) 2011 Red Hat.
* Written by Alon Levy.
*
* This work is licensed under the terms of the GNU GPL, version 2.1 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qemu/units.h"
#include <libcacard.h>
#include "chardev/char-fe.h"
#include "hw/qdev-properties.h"
#include "migration/vmstate.h"
#include "qemu/error-report.h"
#include "qemu/module.h"
#include "qemu/sockets.h"
#include "ccid.h"
#include "qapi/error.h"
#define DPRINTF(card, lvl, fmt, ...) \
do { \
if (lvl <= card->debug) { \
printf("ccid-card-passthru: " fmt , ## __VA_ARGS__); \
} \
} while (0)
#define D_WARN 1
#define D_INFO 2
#define D_MORE_INFO 3
#define D_VERBOSE 4
/* TODO: do we still need this? */
static const 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
};
#define VSCARD_IN_SIZE (64 * KiB)
/* maximum size of ATR - from 7816-3 */
#define MAX_ATR_SIZE 40
typedef struct PassthruState PassthruState;
struct PassthruState {
CCIDCardState base;
CharBackend cs;
uint8_t vscard_in_data[VSCARD_IN_SIZE];
uint32_t vscard_in_pos;
uint32_t vscard_in_hdr;
uint8_t atr[MAX_ATR_SIZE];
uint8_t atr_length;
uint8_t debug;
};
#define TYPE_CCID_PASSTHRU "ccid-card-passthru"
#define PASSTHRU_CCID_CARD(obj) \
OBJECT_CHECK(PassthruState, (obj), TYPE_CCID_PASSTHRU)
/*
* VSCard protocol over chardev
* This code should not depend on the card type.
*/
static void ccid_card_vscard_send_msg(PassthruState *s,
VSCMsgType type, uint32_t reader_id,
const uint8_t *payload, uint32_t length)
{
VSCMsgHeader scr_msg_header;
scr_msg_header.type = htonl(type);
scr_msg_header.reader_id = htonl(reader_id);
scr_msg_header.length = htonl(length);
/* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks */
qemu_chr_fe_write_all(&s->cs, (uint8_t *)&scr_msg_header,
sizeof(VSCMsgHeader));
qemu_chr_fe_write_all(&s->cs, payload, length);
}
static void ccid_card_vscard_send_apdu(PassthruState *s,
const uint8_t *apdu, uint32_t length)
{
ccid_card_vscard_send_msg(
s, VSC_APDU, VSCARD_MINIMAL_READER_ID, apdu, length);
}
static void ccid_card_vscard_send_error(PassthruState *s,
uint32_t reader_id, VSCErrorCode code)
{
VSCMsgError msg = {.code = htonl(code)};
ccid_card_vscard_send_msg(
s, VSC_Error, reader_id, (uint8_t *)&msg, sizeof(msg));
}
static void ccid_card_vscard_send_init(PassthruState *s)
{
VSCMsgInit msg = {
.version = htonl(VSCARD_VERSION),
.magic = VSCARD_MAGIC,
.capabilities = {0}
};
ccid_card_vscard_send_msg(s, VSC_Init, VSCARD_UNDEFINED_READER_ID,
(uint8_t *)&msg, sizeof(msg));
}
static int ccid_card_vscard_can_read(void *opaque)
{
PassthruState *card = opaque;
return VSCARD_IN_SIZE >= card->vscard_in_pos ?
VSCARD_IN_SIZE - card->vscard_in_pos : 0;
}
static void ccid_card_vscard_handle_init(
PassthruState *card, VSCMsgHeader *hdr, VSCMsgInit *init)
{
uint32_t *capabilities;
int num_capabilities;
int i;
capabilities = init->capabilities;
num_capabilities =
1 + ((hdr->length - sizeof(VSCMsgInit)) / sizeof(uint32_t));
init->version = ntohl(init->version);
for (i = 0 ; i < num_capabilities; ++i) {
capabilities[i] = ntohl(capabilities[i]);
}
if (init->magic != VSCARD_MAGIC) {
error_report("wrong magic");
/* we can't disconnect the chardev */
}
if (init->version != VSCARD_VERSION) {
DPRINTF(card, D_WARN,
"got version %d, have %d", init->version, VSCARD_VERSION);
}
/* future handling of capabilities, none exist atm */
ccid_card_vscard_send_init(card);
}
static int check_atr(PassthruState *card, uint8_t *data, int len)
{
int historical_length, opt_bytes;
int td_count = 0;
int td;
if (len < 2) {
return 0;
}
historical_length = data[1] & 0xf;
opt_bytes = 0;
if (data[0] != 0x3b && data[0] != 0x3f) {
DPRINTF(card, D_WARN, "atr's T0 is 0x%X, not in {0x3b, 0x3f}\n",
data[0]);
return 0;
}
td_count = 0;
td = data[1] >> 4;
while (td && td_count < 2 && opt_bytes + historical_length + 2 < len) {
td_count++;
if (td & 0x1) {
opt_bytes++;
}
if (td & 0x2) {
opt_bytes++;
}
if (td & 0x4) {
opt_bytes++;
}
if (td & 0x8) {
opt_bytes++;
td = data[opt_bytes + 2] >> 4;
}
}
if (len < 2 + historical_length + opt_bytes) {
DPRINTF(card, D_WARN,
"atr too short: len %d, but historical_len %d, T1 0x%X\n",
len, historical_length, data[1]);
return 0;
}
if (len > 2 + historical_length + opt_bytes) {
DPRINTF(card, D_WARN,
"atr too long: len %d, but hist/opt %d/%d, T1 0x%X\n",
len, historical_length, opt_bytes, data[1]);
/* let it through */
}
DPRINTF(card, D_VERBOSE,
"atr passes check: %d total length, %d historical, %d optional\n",
len, historical_length, opt_bytes);
return 1;
}
static void ccid_card_vscard_handle_message(PassthruState *card,
VSCMsgHeader *scr_msg_header)
{
uint8_t *data = (uint8_t *)&scr_msg_header[1];
switch (scr_msg_header->type) {
case VSC_ATR:
DPRINTF(card, D_INFO, "VSC_ATR %d\n", scr_msg_header->length);
if (scr_msg_header->length > MAX_ATR_SIZE) {
error_report("ATR size exceeds spec, ignoring");
ccid_card_vscard_send_error(card, scr_msg_header->reader_id,
VSC_GENERAL_ERROR);
break;
}
if (!check_atr(card, data, scr_msg_header->length)) {
error_report("ATR is inconsistent, ignoring");
ccid_card_vscard_send_error(card, scr_msg_header->reader_id,
VSC_GENERAL_ERROR);
break;
}
memcpy(card->atr, data, scr_msg_header->length);
card->atr_length = scr_msg_header->length;
ccid_card_card_inserted(&card->base);
ccid_card_vscard_send_error(card, scr_msg_header->reader_id,
VSC_SUCCESS);
break;
case VSC_APDU:
ccid_card_send_apdu_to_guest(
&card->base, data, scr_msg_header->length);
break;
case VSC_CardRemove:
DPRINTF(card, D_INFO, "VSC_CardRemove\n");
ccid_card_card_removed(&card->base);
ccid_card_vscard_send_error(card,
scr_msg_header->reader_id, VSC_SUCCESS);
break;
case VSC_Init:
ccid_card_vscard_handle_init(
card, scr_msg_header, (VSCMsgInit *)data);
break;
case VSC_Error:
ccid_card_card_error(&card->base, *(uint32_t *)data);
break;
case VSC_ReaderAdd:
if (ccid_card_ccid_attach(&card->base) < 0) {
ccid_card_vscard_send_error(card, VSCARD_UNDEFINED_READER_ID,
VSC_CANNOT_ADD_MORE_READERS);
} else {
ccid_card_vscard_send_error(card, VSCARD_MINIMAL_READER_ID,
VSC_SUCCESS);
}
break;
case VSC_ReaderRemove:
ccid_card_ccid_detach(&card->base);
ccid_card_vscard_send_error(card,
scr_msg_header->reader_id, VSC_SUCCESS);
break;
default:
printf("usb-ccid: chardev: unexpected message of type %X\n",
scr_msg_header->type);
ccid_card_vscard_send_error(card, scr_msg_header->reader_id,
VSC_GENERAL_ERROR);
}
}
static void ccid_card_vscard_drop_connection(PassthruState *card)
{
qemu_chr_fe_deinit(&card->cs, true);
card->vscard_in_pos = card->vscard_in_hdr = 0;
}
static void ccid_card_vscard_read(void *opaque, const uint8_t *buf, int size)
{
PassthruState *card = opaque;
VSCMsgHeader *hdr;
if (card->vscard_in_pos + size > VSCARD_IN_SIZE) {
error_report("no room for data: pos %u + size %d > %" PRId64 "."
" dropping connection.",
card->vscard_in_pos, size, VSCARD_IN_SIZE);
ccid_card_vscard_drop_connection(card);
return;
}
assert(card->vscard_in_pos < VSCARD_IN_SIZE);
assert(card->vscard_in_hdr < VSCARD_IN_SIZE);
memcpy(card->vscard_in_data + card->vscard_in_pos, buf, size);
card->vscard_in_pos += size;
hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr);
while ((card->vscard_in_pos - card->vscard_in_hdr >= sizeof(VSCMsgHeader))
&&(card->vscard_in_pos - card->vscard_in_hdr >=
sizeof(VSCMsgHeader) + ntohl(hdr->length))) {
hdr->reader_id = ntohl(hdr->reader_id);
hdr->length = ntohl(hdr->length);
hdr->type = ntohl(hdr->type);
ccid_card_vscard_handle_message(card, hdr);
card->vscard_in_hdr += hdr->length + sizeof(VSCMsgHeader);
hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr);
}
if (card->vscard_in_hdr == card->vscard_in_pos) {
card->vscard_in_pos = card->vscard_in_hdr = 0;
}
}
static void ccid_card_vscard_event(void *opaque, QEMUChrEvent event)
{
PassthruState *card = opaque;
switch (event) {
case CHR_EVENT_BREAK:
card->vscard_in_pos = card->vscard_in_hdr = 0;
break;
case CHR_EVENT_OPENED:
DPRINTF(card, D_INFO, "%s: CHR_EVENT_OPENED\n", __func__);
break;
case CHR_EVENT_MUX_IN:
case CHR_EVENT_MUX_OUT:
case CHR_EVENT_CLOSED:
/* Ignore */
break;
}
}
/* End VSCard handling */
static void passthru_apdu_from_guest(
CCIDCardState *base, const uint8_t *apdu, uint32_t len)
{
PassthruState *card = PASSTHRU_CCID_CARD(base);
if (!qemu_chr_fe_backend_connected(&card->cs)) {
printf("ccid-passthru: no chardev, discarding apdu length %d\n", len);
return;
}
ccid_card_vscard_send_apdu(card, apdu, len);
}
static const uint8_t *passthru_get_atr(CCIDCardState *base, uint32_t *len)
{
PassthruState *card = PASSTHRU_CCID_CARD(base);
*len = card->atr_length;
return card->atr;
}
static void passthru_realize(CCIDCardState *base, Error **errp)
{
PassthruState *card = PASSTHRU_CCID_CARD(base);
card->vscard_in_pos = 0;
card->vscard_in_hdr = 0;
if (qemu_chr_fe_backend_connected(&card->cs)) {
DPRINTF(card, D_INFO, "ccid-card-passthru: initing chardev");
qemu_chr_fe_set_handlers(&card->cs,
ccid_card_vscard_can_read,
ccid_card_vscard_read,
ccid_card_vscard_event, NULL, card, NULL, true);
ccid_card_vscard_send_init(card);
} else {
error_setg(errp, "missing chardev");
return;
}
card->debug = parse_debug_env("QEMU_CCID_PASSTHRU_DEBUG", D_VERBOSE,
card->debug);
assert(sizeof(DEFAULT_ATR) <= MAX_ATR_SIZE);
memcpy(card->atr, DEFAULT_ATR, sizeof(DEFAULT_ATR));
card->atr_length = sizeof(DEFAULT_ATR);
}
static VMStateDescription passthru_vmstate = {
.name = "ccid-card-passthru",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_BUFFER(vscard_in_data, PassthruState),
VMSTATE_UINT32(vscard_in_pos, PassthruState),
VMSTATE_UINT32(vscard_in_hdr, PassthruState),
VMSTATE_BUFFER(atr, PassthruState),
VMSTATE_UINT8(atr_length, PassthruState),
VMSTATE_END_OF_LIST()
}
};
static Property passthru_card_properties[] = {
DEFINE_PROP_CHR("chardev", PassthruState, cs),
DEFINE_PROP_UINT8("debug", PassthruState, debug, 0),
DEFINE_PROP_END_OF_LIST(),
};
static void passthru_class_initfn(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
CCIDCardClass *cc = CCID_CARD_CLASS(klass);
cc->realize = passthru_realize;
cc->get_atr = passthru_get_atr;
cc->apdu_from_guest = passthru_apdu_from_guest;
set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
dc->desc = "passthrough smartcard";
dc->vmsd = &passthru_vmstate;
device_class_set_props(dc, passthru_card_properties);
}
static const TypeInfo passthru_card_info = {
.name = TYPE_CCID_PASSTHRU,
.parent = TYPE_CCID_CARD,
.instance_size = sizeof(PassthruState),
.class_init = passthru_class_initfn,
};
static void ccid_card_passthru_register_types(void)
{
type_register_static(&passthru_card_info);
}
type_init(ccid_card_passthru_register_types)