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