hw/ccid-card-passthru.c

   1 /*
   2  * CCID Passthru Card Device emulation
   3  *
   4  * Copyright (c) 2011 Red Hat.
   5  * Written by Alon Levy.
   6  *
   7  * This work is licensed under the terms of the GNU GPL, version 2.1 or later.
   8  * See the COPYING file in the top-level directory.
   9  */
  10
  11 #include "qemu-char.h"
  12 #include "qemu_socket.h"
  13 #include "monitor.h"
  14 #include "hw/ccid.h"
  15 #include "libcacard/vscard_common.h"
  16
  17 #define DPRINTF(card, lvl, fmt, ...)                    \
  18 do {                                                    \
  19     if (lvl <= card->debug) {                           \
  20         printf("ccid-card-passthru: " fmt , ## __VA_ARGS__);     \
  21     }                                                   \
  22 } while (0)
  23
  24 #define D_WARN 1
  25 #define D_INFO 2
  26 #define D_MORE_INFO 3
  27 #define D_VERBOSE 4
  28
  29 /* TODO: do we still need this? */
  30 uint8_t DEFAULT_ATR[] = {
  31 /*
  32  * From some example somewhere
  33  * 0x3B, 0xB0, 0x18, 0x00, 0xD1, 0x81, 0x05, 0xB1, 0x40, 0x38, 0x1F, 0x03, 0x28
  34  */
  35
  36 /* From an Athena smart card */
  37  0x3B, 0xD5, 0x18, 0xFF, 0x80, 0x91, 0xFE, 0x1F, 0xC3, 0x80, 0x73, 0xC8, 0x21,
  38  0x13, 0x08
  39 };
  40
  41
  42 #define PASSTHRU_DEV_NAME "ccid-card-passthru"
  43 #define VSCARD_IN_SIZE 65536
  44
  45 /* maximum size of ATR - from 7816-3 */
  46 #define MAX_ATR_SIZE        40
  47
  48 typedef struct PassthruState PassthruState;
  49
  50 struct PassthruState {
  51     CCIDCardState base;
  52     CharDriverState *cs;
  53     uint8_t  vscard_in_data[VSCARD_IN_SIZE];
  54     uint32_t vscard_in_pos;
  55     uint32_t vscard_in_hdr;
  56     uint8_t  atr[MAX_ATR_SIZE];
  57     uint8_t  atr_length;
  58     uint8_t  debug;
  59 };
  60
  61 static void ccid_card_vscard_update_handlers(PassthruState *card);
  62
  63 /*
  64  * VSCard protocol over chardev
  65  * This code should not depend on the card type.
  66  */
  67
  68 static void ccid_card_vscard_send_msg(PassthruState *s,
  69         VSCMsgType type, uint32_t reader_id,
  70         const uint8_t *payload, uint32_t length)
  71 {
  72     VSCMsgHeader scr_msg_header;
  73
  74     scr_msg_header.type = htonl(type);
  75     scr_msg_header.reader_id = htonl(reader_id);
  76     scr_msg_header.length = htonl(length);
  77     qemu_chr_fe_write(s->cs, (uint8_t *)&scr_msg_header, sizeof(VSCMsgHeader));
  78     qemu_chr_fe_write(s->cs, payload, length);
  79 }
  80
  81 static void ccid_card_vscard_send_apdu(PassthruState *s,
  82     const uint8_t *apdu, uint32_t length)
  83 {
  84     ccid_card_vscard_send_msg(
  85         s, VSC_APDU, VSCARD_MINIMAL_READER_ID, apdu, length);
  86 }
  87
  88 static void ccid_card_vscard_send_error(PassthruState *s,
  89                     uint32_t reader_id, VSCErrorCode code)
  90 {
  91     VSCMsgError msg = {.code = htonl(code)};
  92
  93     ccid_card_vscard_send_msg(
  94         s, VSC_Error, reader_id, (uint8_t *)&msg, sizeof(msg));
  95 }
  96
  97 static void ccid_card_vscard_send_init(PassthruState *s)
  98 {
  99     VSCMsgInit msg = {
 100         .version = htonl(VSCARD_VERSION),
 101         .magic = VSCARD_MAGIC,
 102         .capabilities = {0}
 103     };
 104
 105     ccid_card_vscard_send_msg(s, VSC_Init, VSCARD_UNDEFINED_READER_ID,
 106                          (uint8_t *)&msg, sizeof(msg));
 107 }
 108
 109 static int ccid_card_vscard_can_read(PassthruState *card)
 110 {
 111     return VSCARD_IN_SIZE >= card->vscard_in_pos ?
 112            VSCARD_IN_SIZE - card->vscard_in_pos : 0;
 113 }
 114
 115 static void ccid_card_vscard_handle_init(
 116     PassthruState *card, VSCMsgHeader *hdr, VSCMsgInit *init)
 117 {
 118     uint32_t *capabilities;
 119     int num_capabilities;
 120     int i;
 121
 122     capabilities = init->capabilities;
 123     num_capabilities =
 124         1 + ((hdr->length - sizeof(VSCMsgInit)) / sizeof(uint32_t));
 125     init->version = ntohl(init->version);
 126     for (i = 0 ; i < num_capabilities; ++i) {
 127         capabilities[i] = ntohl(capabilities[i]);
 128     }
 129     if (init->magic != VSCARD_MAGIC) {
 130         error_report("wrong magic");
 131         /* we can't disconnect the chardev */
 132     }
 133     if (init->version != VSCARD_VERSION) {
 134         DPRINTF(card, D_WARN,
 135             "got version %d, have %d", init->version, VSCARD_VERSION);
 136     }
 137     /* future handling of capabilities, none exist atm */
 138     ccid_card_vscard_send_init(card);
 139 }
 140
 141 static void ccid_card_vscard_handle_message(PassthruState *card,
 142     VSCMsgHeader *scr_msg_header)
 143 {
 144     uint8_t *data = (uint8_t *)&scr_msg_header[1];
 145
 146     switch (scr_msg_header->type) {
 147     case VSC_ATR:
 148         DPRINTF(card, D_INFO, "VSC_ATR %d\n", scr_msg_header->length);
 149         if (scr_msg_header->length > MAX_ATR_SIZE) {
 150             error_report("ATR size exceeds spec, ignoring");
 151             ccid_card_vscard_send_error(card, scr_msg_header->reader_id,
 152                                         VSC_GENERAL_ERROR);
 153         }
 154         memcpy(card->atr, data, scr_msg_header->length);
 155         card->atr_length = scr_msg_header->length;
 156         ccid_card_card_inserted(&card->base);
 157         ccid_card_vscard_send_error(card, scr_msg_header->reader_id,
 158                                     VSC_SUCCESS);
 159         break;
 160     case VSC_APDU:
 161         ccid_card_send_apdu_to_guest(
 162             &card->base, data, scr_msg_header->length);
 163         break;
 164     case VSC_CardRemove:
 165         DPRINTF(card, D_INFO, "VSC_CardRemove\n");
 166         ccid_card_card_removed(&card->base);
 167         ccid_card_vscard_send_error(card,
 168             scr_msg_header->reader_id, VSC_SUCCESS);
 169         break;
 170     case VSC_Init:
 171         ccid_card_vscard_handle_init(
 172             card, scr_msg_header, (VSCMsgInit *)data);
 173         break;
 174     case VSC_Error:
 175         ccid_card_card_error(&card->base, *(uint32_t *)data);
 176         break;
 177     case VSC_ReaderAdd:
 178         if (ccid_card_ccid_attach(&card->base) < 0) {
 179             ccid_card_vscard_send_error(card, VSCARD_UNDEFINED_READER_ID,
 180                                       VSC_CANNOT_ADD_MORE_READERS);
 181         } else {
 182             ccid_card_vscard_send_error(card, VSCARD_MINIMAL_READER_ID,
 183                                         VSC_SUCCESS);
 184         }
 185         break;
 186     case VSC_ReaderRemove:
 187         ccid_card_ccid_detach(&card->base);
 188         ccid_card_vscard_send_error(card,
 189             scr_msg_header->reader_id, VSC_SUCCESS);
 190         break;
 191     default:
 192         printf("usb-ccid: chardev: unexpected message of type %X\n",
 193                scr_msg_header->type);
 194         ccid_card_vscard_send_error(card, scr_msg_header->reader_id,
 195             VSC_GENERAL_ERROR);
 196     }
 197 }
 198
 199 static void ccid_card_vscard_drop_connection(PassthruState *card)
 200 {
 201     qemu_chr_fe_delete(card->cs);
 202     card->vscard_in_pos = card->vscard_in_hdr = 0;
 203     ccid_card_vscard_update_handlers(card);
 204 }
 205
 206 static void ccid_card_vscard_read(PassthruState *card, const uint8_t *buf, int size)
 207 {
 208     VSCMsgHeader *hdr;
 209
 210     if (card->vscard_in_pos + size > VSCARD_IN_SIZE) {
 211         error_report(
 212             "no room for data: pos %d +  size %d > %d. dropping connection.",
 213             card->vscard_in_pos, size, VSCARD_IN_SIZE);
 214         ccid_card_vscard_drop_connection(card);
 215         return;
 216     }
 217     assert(card->vscard_in_pos < VSCARD_IN_SIZE);
 218     assert(card->vscard_in_hdr < VSCARD_IN_SIZE);
 219     memcpy(card->vscard_in_data + card->vscard_in_pos, buf, size);
 220     card->vscard_in_pos += size;
 221     hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr);
 222
 223     while ((card->vscard_in_pos - card->vscard_in_hdr >= sizeof(VSCMsgHeader))
 224          &&(card->vscard_in_pos - card->vscard_in_hdr >=
 225                                   sizeof(VSCMsgHeader) + ntohl(hdr->length))) {
 226         hdr->reader_id = ntohl(hdr->reader_id);
 227         hdr->length = ntohl(hdr->length);
 228         hdr->type = ntohl(hdr->type);
 229         ccid_card_vscard_handle_message(card, hdr);
 230         card->vscard_in_hdr += hdr->length + sizeof(VSCMsgHeader);
 231         hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr);
 232     }
 233     if (card->vscard_in_hdr == card->vscard_in_pos) {
 234         card->vscard_in_pos = card->vscard_in_hdr = 0;
 235     }
 236     ccid_card_vscard_update_handlers(card);
 237 }
 238
 239 static int ccid_card_vscard_event(void *opaque, int event, void *data)
 240 {
 241     PassthruState *card = opaque;
 242
 243     switch (event) {
 244     case CHR_EVENT_BREAK:
 245         card->vscard_in_pos = card->vscard_in_hdr = 0;
 246         ccid_card_vscard_update_handlers(card);
 247         break;
 248     case CHR_EVENT_FOCUS:
 249         break;
 250     case CHR_EVENT_OPENED:
 251         DPRINTF(card, D_INFO, "%s: CHR_EVENT_OPENED\n", __func__);
 252         break;
 253     }
 254     return 0;
 255 }
 256
 257 static void ccid_card_vscard_read_handler(void *opaque)
 258 {
 259     PassthruState *card = opaque;
 260     uint8_t buf[32];
 261     int size;
 262
 263     size = ccid_card_vscard_can_read(card);
 264     size = MIN(size, sizeof(buf));
 265     size = qemu_chr_fe_read(card->cs, buf, size);
 266
 267     ccid_card_vscard_read(card, buf, size);
 268 }
 269
 270 static void ccid_card_vscard_update_handlers(PassthruState *card)
 271 {
 272     if (ccid_card_vscard_can_read(card) > 0) {
 273         qemu_chr_fe_set_handlers(card->cs,
 274                                  ccid_card_vscard_read_handler,
 275                                  NULL,
 276                                  ccid_card_vscard_event, card);
 277     } else {
 278         qemu_chr_fe_set_handlers(card->cs,
 279                                  NULL, NULL,
 280                                  ccid_card_vscard_event, card);
 281     }
 282 }
 283
 284 /* End VSCard handling */
 285
 286 static void passthru_apdu_from_guest(
 287     CCIDCardState *base, const uint8_t *apdu, uint32_t len)
 288 {
 289     PassthruState *card = DO_UPCAST(PassthruState, base, base);
 290
 291     if (!card->cs) {
 292         printf("ccid-passthru: no chardev, discarding apdu length %d\n", len);
 293         return;
 294     }
 295     ccid_card_vscard_send_apdu(card, apdu, len);
 296 }
 297
 298 static const uint8_t *passthru_get_atr(CCIDCardState *base, uint32_t *len)
 299 {
 300     PassthruState *card = DO_UPCAST(PassthruState, base, base);
 301
 302     *len = card->atr_length;
 303     return card->atr;
 304 }
 305
 306 static int passthru_initfn(CCIDCardState *base)
 307 {
 308     PassthruState *card = DO_UPCAST(PassthruState, base, base);
 309
 310     card->vscard_in_pos = 0;
 311     card->vscard_in_hdr = 0;
 312     if (card->cs) {
 313         DPRINTF(card, D_INFO, "initing chardev\n");
 314         qemu_chr_fe_open(card->cs);
 315         ccid_card_vscard_update_handlers(card);
 316     } else {
 317         error_report("missing chardev");
 318         return -1;
 319     }
 320     assert(sizeof(DEFAULT_ATR) <= MAX_ATR_SIZE);
 321     memcpy(card->atr, DEFAULT_ATR, sizeof(DEFAULT_ATR));
 322     card->atr_length = sizeof(DEFAULT_ATR);
 323     return 0;
 324 }
 325
 326 static int passthru_exitfn(CCIDCardState *base)
 327 {
 328     return 0;
 329 }
 330
 331 static VMStateDescription passthru_vmstate = {
 332     .name = PASSTHRU_DEV_NAME,
 333     .version_id = 1,
 334     .minimum_version_id = 1,
 335     .fields = (VMStateField[]) {
 336         VMSTATE_BUFFER(vscard_in_data, PassthruState),
 337         VMSTATE_UINT32(vscard_in_pos, PassthruState),
 338         VMSTATE_UINT32(vscard_in_hdr, PassthruState),
 339         VMSTATE_BUFFER(atr, PassthruState),
 340         VMSTATE_UINT8(atr_length, PassthruState),
 341         VMSTATE_END_OF_LIST()
 342     }
 343 };
 344
 345 static CCIDCardInfo passthru_card_info = {
 346     .qdev.name = PASSTHRU_DEV_NAME,
 347     .qdev.desc = "passthrough smartcard",
 348     .qdev.size = sizeof(PassthruState),
 349     .qdev.vmsd = &passthru_vmstate,
 350     .initfn = passthru_initfn,
 351     .exitfn = passthru_exitfn,
 352     .get_atr = passthru_get_atr,
 353     .apdu_from_guest = passthru_apdu_from_guest,
 354     .qdev.props     = (Property[]) {
 355         DEFINE_PROP_CHR("chardev", PassthruState, cs),
 356         DEFINE_PROP_UINT8("debug", PassthruState, debug, 0),
 357         DEFINE_PROP_END_OF_LIST(),
 358     },
 359 };
 360
 361 static void ccid_card_passthru_register_devices(void)
 362 {
 363     ccid_card_qdev_register(&passthru_card_info);
 364 }
 365
 366 device_init(ccid_card_passthru_register_devices)