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/osdep.h" 12 #include "qemu-common.h" 13 #include "qemu/units.h" 14 #include <libcacard.h> 15 #include "chardev/char-fe.h" 16 #include "hw/qdev-properties.h" 17 #include "hw/qdev-properties-system.h" 18 #include "migration/vmstate.h" 19 #include "qemu/error-report.h" 20 #include "qemu/module.h" 21 #include "qemu/sockets.h" 22 #include "ccid.h" 23 #include "qapi/error.h" 24 #include "qom/object.h" 25 26 #define DPRINTF(card, lvl, fmt, ...) \ 27 do { \ 28 if (lvl <= card->debug) { \ 29 printf("ccid-card-passthru: " fmt , ## __VA_ARGS__); \ 30 } \ 31 } while (0) 32 33 #define D_WARN 1 34 #define D_INFO 2 35 #define D_MORE_INFO 3 36 #define D_VERBOSE 4 37 38 /* TODO: do we still need this? */ 39 static const uint8_t DEFAULT_ATR[] = { 40 /* 41 * From some example somewhere 42 * 0x3B, 0xB0, 0x18, 0x00, 0xD1, 0x81, 0x05, 0xB1, 0x40, 0x38, 0x1F, 0x03, 0x28 43 */ 44 45 /* From an Athena smart card */ 46 0x3B, 0xD5, 0x18, 0xFF, 0x80, 0x91, 0xFE, 0x1F, 0xC3, 0x80, 0x73, 0xC8, 0x21, 47 0x13, 0x08 48 }; 49 50 #define VSCARD_IN_SIZE (64 * KiB) 51 52 /* maximum size of ATR - from 7816-3 */ 53 #define MAX_ATR_SIZE 40 54 55 typedef struct PassthruState PassthruState; 56 57 struct PassthruState { 58 CCIDCardState base; 59 CharBackend cs; 60 uint8_t vscard_in_data[VSCARD_IN_SIZE]; 61 uint32_t vscard_in_pos; 62 uint32_t vscard_in_hdr; 63 uint8_t atr[MAX_ATR_SIZE]; 64 uint8_t atr_length; 65 uint8_t debug; 66 }; 67 68 #define TYPE_CCID_PASSTHRU "ccid-card-passthru" 69 DECLARE_INSTANCE_CHECKER(PassthruState, PASSTHRU_CCID_CARD, 70 TYPE_CCID_PASSTHRU) 71 72 /* 73 * VSCard protocol over chardev 74 * This code should not depend on the card type. 75 */ 76 77 static void ccid_card_vscard_send_msg(PassthruState *s, 78 VSCMsgType type, uint32_t reader_id, 79 const uint8_t *payload, uint32_t length) 80 { 81 VSCMsgHeader scr_msg_header; 82 83 scr_msg_header.type = htonl(type); 84 scr_msg_header.reader_id = htonl(reader_id); 85 scr_msg_header.length = htonl(length); 86 /* XXX this blocks entire thread. Rewrite to use 87 * qemu_chr_fe_write and background I/O callbacks */ 88 qemu_chr_fe_write_all(&s->cs, (uint8_t *)&scr_msg_header, 89 sizeof(VSCMsgHeader)); 90 qemu_chr_fe_write_all(&s->cs, payload, length); 91 } 92 93 static void ccid_card_vscard_send_apdu(PassthruState *s, 94 const uint8_t *apdu, uint32_t length) 95 { 96 ccid_card_vscard_send_msg( 97 s, VSC_APDU, VSCARD_MINIMAL_READER_ID, apdu, length); 98 } 99 100 static void ccid_card_vscard_send_error(PassthruState *s, 101 uint32_t reader_id, VSCErrorCode code) 102 { 103 VSCMsgError msg = {.code = htonl(code)}; 104 105 ccid_card_vscard_send_msg( 106 s, VSC_Error, reader_id, (uint8_t *)&msg, sizeof(msg)); 107 } 108 109 static void ccid_card_vscard_send_init(PassthruState *s) 110 { 111 VSCMsgInit msg = { 112 .version = htonl(VSCARD_VERSION), 113 .magic = VSCARD_MAGIC, 114 .capabilities = {0} 115 }; 116 117 ccid_card_vscard_send_msg(s, VSC_Init, VSCARD_UNDEFINED_READER_ID, 118 (uint8_t *)&msg, sizeof(msg)); 119 } 120 121 static int ccid_card_vscard_can_read(void *opaque) 122 { 123 PassthruState *card = opaque; 124 125 return VSCARD_IN_SIZE >= card->vscard_in_pos ? 126 VSCARD_IN_SIZE - card->vscard_in_pos : 0; 127 } 128 129 static void ccid_card_vscard_handle_init( 130 PassthruState *card, VSCMsgHeader *hdr, VSCMsgInit *init) 131 { 132 uint32_t *capabilities; 133 int num_capabilities; 134 int i; 135 136 capabilities = init->capabilities; 137 num_capabilities = 138 1 + ((hdr->length - sizeof(VSCMsgInit)) / sizeof(uint32_t)); 139 init->version = ntohl(init->version); 140 for (i = 0 ; i < num_capabilities; ++i) { 141 capabilities[i] = ntohl(capabilities[i]); 142 } 143 if (init->magic != VSCARD_MAGIC) { 144 error_report("wrong magic"); 145 /* we can't disconnect the chardev */ 146 } 147 if (init->version != VSCARD_VERSION) { 148 DPRINTF(card, D_WARN, 149 "got version %d, have %d", init->version, VSCARD_VERSION); 150 } 151 /* future handling of capabilities, none exist atm */ 152 ccid_card_vscard_send_init(card); 153 } 154 155 static int check_atr(PassthruState *card, uint8_t *data, int len) 156 { 157 int historical_length, opt_bytes; 158 int td_count = 0; 159 int td; 160 161 if (len < 2) { 162 return 0; 163 } 164 historical_length = data[1] & 0xf; 165 opt_bytes = 0; 166 if (data[0] != 0x3b && data[0] != 0x3f) { 167 DPRINTF(card, D_WARN, "atr's T0 is 0x%X, not in {0x3b, 0x3f}\n", 168 data[0]); 169 return 0; 170 } 171 td_count = 0; 172 td = data[1] >> 4; 173 while (td && td_count < 2 && opt_bytes + historical_length + 2 < len) { 174 td_count++; 175 if (td & 0x1) { 176 opt_bytes++; 177 } 178 if (td & 0x2) { 179 opt_bytes++; 180 } 181 if (td & 0x4) { 182 opt_bytes++; 183 } 184 if (td & 0x8) { 185 opt_bytes++; 186 td = data[opt_bytes + 2] >> 4; 187 } 188 } 189 if (len < 2 + historical_length + opt_bytes) { 190 DPRINTF(card, D_WARN, 191 "atr too short: len %d, but historical_len %d, T1 0x%X\n", 192 len, historical_length, data[1]); 193 return 0; 194 } 195 if (len > 2 + historical_length + opt_bytes) { 196 DPRINTF(card, D_WARN, 197 "atr too long: len %d, but hist/opt %d/%d, T1 0x%X\n", 198 len, historical_length, opt_bytes, data[1]); 199 /* let it through */ 200 } 201 DPRINTF(card, D_VERBOSE, 202 "atr passes check: %d total length, %d historical, %d optional\n", 203 len, historical_length, opt_bytes); 204 205 return 1; 206 } 207 208 static void ccid_card_vscard_handle_message(PassthruState *card, 209 VSCMsgHeader *scr_msg_header) 210 { 211 uint8_t *data = (uint8_t *)&scr_msg_header[1]; 212 213 switch (scr_msg_header->type) { 214 case VSC_ATR: 215 DPRINTF(card, D_INFO, "VSC_ATR %d\n", scr_msg_header->length); 216 if (scr_msg_header->length > MAX_ATR_SIZE) { 217 error_report("ATR size exceeds spec, ignoring"); 218 ccid_card_vscard_send_error(card, scr_msg_header->reader_id, 219 VSC_GENERAL_ERROR); 220 break; 221 } 222 if (!check_atr(card, data, scr_msg_header->length)) { 223 error_report("ATR is inconsistent, ignoring"); 224 ccid_card_vscard_send_error(card, scr_msg_header->reader_id, 225 VSC_GENERAL_ERROR); 226 break; 227 } 228 memcpy(card->atr, data, scr_msg_header->length); 229 card->atr_length = scr_msg_header->length; 230 ccid_card_card_inserted(&card->base); 231 ccid_card_vscard_send_error(card, scr_msg_header->reader_id, 232 VSC_SUCCESS); 233 break; 234 case VSC_APDU: 235 ccid_card_send_apdu_to_guest( 236 &card->base, data, scr_msg_header->length); 237 break; 238 case VSC_CardRemove: 239 DPRINTF(card, D_INFO, "VSC_CardRemove\n"); 240 ccid_card_card_removed(&card->base); 241 ccid_card_vscard_send_error(card, 242 scr_msg_header->reader_id, VSC_SUCCESS); 243 break; 244 case VSC_Init: 245 ccid_card_vscard_handle_init( 246 card, scr_msg_header, (VSCMsgInit *)data); 247 break; 248 case VSC_Error: 249 ccid_card_card_error(&card->base, *(uint32_t *)data); 250 break; 251 case VSC_ReaderAdd: 252 if (ccid_card_ccid_attach(&card->base) < 0) { 253 ccid_card_vscard_send_error(card, VSCARD_UNDEFINED_READER_ID, 254 VSC_CANNOT_ADD_MORE_READERS); 255 } else { 256 ccid_card_vscard_send_error(card, VSCARD_MINIMAL_READER_ID, 257 VSC_SUCCESS); 258 } 259 break; 260 case VSC_ReaderRemove: 261 ccid_card_ccid_detach(&card->base); 262 ccid_card_vscard_send_error(card, 263 scr_msg_header->reader_id, VSC_SUCCESS); 264 break; 265 default: 266 printf("usb-ccid: chardev: unexpected message of type %X\n", 267 scr_msg_header->type); 268 ccid_card_vscard_send_error(card, scr_msg_header->reader_id, 269 VSC_GENERAL_ERROR); 270 } 271 } 272 273 static void ccid_card_vscard_drop_connection(PassthruState *card) 274 { 275 qemu_chr_fe_deinit(&card->cs, true); 276 card->vscard_in_pos = card->vscard_in_hdr = 0; 277 } 278 279 static void ccid_card_vscard_read(void *opaque, const uint8_t *buf, int size) 280 { 281 PassthruState *card = opaque; 282 VSCMsgHeader *hdr; 283 284 if (card->vscard_in_pos + size > VSCARD_IN_SIZE) { 285 error_report("no room for data: pos %u + size %d > %" PRId64 "." 286 " dropping connection.", 287 card->vscard_in_pos, size, VSCARD_IN_SIZE); 288 ccid_card_vscard_drop_connection(card); 289 return; 290 } 291 assert(card->vscard_in_pos < VSCARD_IN_SIZE); 292 assert(card->vscard_in_hdr < VSCARD_IN_SIZE); 293 memcpy(card->vscard_in_data + card->vscard_in_pos, buf, size); 294 card->vscard_in_pos += size; 295 hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr); 296 297 while ((card->vscard_in_pos - card->vscard_in_hdr >= sizeof(VSCMsgHeader)) 298 &&(card->vscard_in_pos - card->vscard_in_hdr >= 299 sizeof(VSCMsgHeader) + ntohl(hdr->length))) { 300 hdr->reader_id = ntohl(hdr->reader_id); 301 hdr->length = ntohl(hdr->length); 302 hdr->type = ntohl(hdr->type); 303 ccid_card_vscard_handle_message(card, hdr); 304 card->vscard_in_hdr += hdr->length + sizeof(VSCMsgHeader); 305 hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr); 306 } 307 if (card->vscard_in_hdr == card->vscard_in_pos) { 308 card->vscard_in_pos = card->vscard_in_hdr = 0; 309 } 310 } 311 312 static void ccid_card_vscard_event(void *opaque, QEMUChrEvent event) 313 { 314 PassthruState *card = opaque; 315 316 switch (event) { 317 case CHR_EVENT_BREAK: 318 card->vscard_in_pos = card->vscard_in_hdr = 0; 319 break; 320 case CHR_EVENT_OPENED: 321 DPRINTF(card, D_INFO, "%s: CHR_EVENT_OPENED\n", __func__); 322 break; 323 case CHR_EVENT_MUX_IN: 324 case CHR_EVENT_MUX_OUT: 325 case CHR_EVENT_CLOSED: 326 /* Ignore */ 327 break; 328 } 329 } 330 331 /* End VSCard handling */ 332 333 static void passthru_apdu_from_guest( 334 CCIDCardState *base, const uint8_t *apdu, uint32_t len) 335 { 336 PassthruState *card = PASSTHRU_CCID_CARD(base); 337 338 if (!qemu_chr_fe_backend_connected(&card->cs)) { 339 printf("ccid-passthru: no chardev, discarding apdu length %u\n", len); 340 return; 341 } 342 ccid_card_vscard_send_apdu(card, apdu, len); 343 } 344 345 static const uint8_t *passthru_get_atr(CCIDCardState *base, uint32_t *len) 346 { 347 PassthruState *card = PASSTHRU_CCID_CARD(base); 348 349 *len = card->atr_length; 350 return card->atr; 351 } 352 353 static void passthru_realize(CCIDCardState *base, Error **errp) 354 { 355 PassthruState *card = PASSTHRU_CCID_CARD(base); 356 357 card->vscard_in_pos = 0; 358 card->vscard_in_hdr = 0; 359 if (qemu_chr_fe_backend_connected(&card->cs)) { 360 DPRINTF(card, D_INFO, "ccid-card-passthru: initing chardev"); 361 qemu_chr_fe_set_handlers(&card->cs, 362 ccid_card_vscard_can_read, 363 ccid_card_vscard_read, 364 ccid_card_vscard_event, NULL, card, NULL, true); 365 ccid_card_vscard_send_init(card); 366 } else { 367 error_setg(errp, "missing chardev"); 368 return; 369 } 370 card->debug = parse_debug_env("QEMU_CCID_PASSTHRU_DEBUG", D_VERBOSE, 371 card->debug); 372 assert(sizeof(DEFAULT_ATR) <= MAX_ATR_SIZE); 373 memcpy(card->atr, DEFAULT_ATR, sizeof(DEFAULT_ATR)); 374 card->atr_length = sizeof(DEFAULT_ATR); 375 } 376 377 static const VMStateDescription passthru_vmstate = { 378 .name = "ccid-card-passthru", 379 .version_id = 1, 380 .minimum_version_id = 1, 381 .fields = (VMStateField[]) { 382 VMSTATE_BUFFER(vscard_in_data, PassthruState), 383 VMSTATE_UINT32(vscard_in_pos, PassthruState), 384 VMSTATE_UINT32(vscard_in_hdr, PassthruState), 385 VMSTATE_BUFFER(atr, PassthruState), 386 VMSTATE_UINT8(atr_length, PassthruState), 387 VMSTATE_END_OF_LIST() 388 } 389 }; 390 391 static Property passthru_card_properties[] = { 392 DEFINE_PROP_CHR("chardev", PassthruState, cs), 393 DEFINE_PROP_UINT8("debug", PassthruState, debug, 0), 394 DEFINE_PROP_END_OF_LIST(), 395 }; 396 397 static void passthru_class_initfn(ObjectClass *klass, void *data) 398 { 399 DeviceClass *dc = DEVICE_CLASS(klass); 400 CCIDCardClass *cc = CCID_CARD_CLASS(klass); 401 402 cc->realize = passthru_realize; 403 cc->get_atr = passthru_get_atr; 404 cc->apdu_from_guest = passthru_apdu_from_guest; 405 set_bit(DEVICE_CATEGORY_INPUT, dc->categories); 406 dc->desc = "passthrough smartcard"; 407 dc->vmsd = &passthru_vmstate; 408 device_class_set_props(dc, passthru_card_properties); 409 } 410 411 static const TypeInfo passthru_card_info = { 412 .name = TYPE_CCID_PASSTHRU, 413 .parent = TYPE_CCID_CARD, 414 .instance_size = sizeof(PassthruState), 415 .class_init = passthru_class_initfn, 416 }; 417 418 static void ccid_card_passthru_register_types(void) 419 { 420 type_register_static(&passthru_card_info); 421 } 422 423 type_init(ccid_card_passthru_register_types) 424