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