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