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