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