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