/* * CCID Passthru Card Device emulation * * Copyright (c) 2011 Red Hat. * Written by Alon Levy. * * This work is licensed under the terms of the GNU GPL, version 2.1 or later. * See the COPYING file in the top-level directory. */ #include "qemu/osdep.h" #include "qemu/cutils.h" #include "qemu/units.h" #include #include "chardev/char-fe.h" #include "hw/qdev-properties.h" #include "hw/qdev-properties-system.h" #include "migration/vmstate.h" #include "qemu/error-report.h" #include "qemu/module.h" #include "qemu/sockets.h" #include "ccid.h" #include "qapi/error.h" #include "qom/object.h" #define DPRINTF(card, lvl, fmt, ...) \ do { \ if (lvl <= card->debug) { \ printf("ccid-card-passthru: " fmt , ## __VA_ARGS__); \ } \ } while (0) #define D_WARN 1 #define D_INFO 2 #define D_MORE_INFO 3 #define D_VERBOSE 4 /* TODO: do we still need this? */ static const uint8_t DEFAULT_ATR[] = { /* * From some example somewhere * 0x3B, 0xB0, 0x18, 0x00, 0xD1, 0x81, 0x05, 0xB1, 0x40, 0x38, 0x1F, 0x03, 0x28 */ /* From an Athena smart card */ 0x3B, 0xD5, 0x18, 0xFF, 0x80, 0x91, 0xFE, 0x1F, 0xC3, 0x80, 0x73, 0xC8, 0x21, 0x13, 0x08 }; #define VSCARD_IN_SIZE (64 * KiB) /* maximum size of ATR - from 7816-3 */ #define MAX_ATR_SIZE 40 typedef struct PassthruState PassthruState; struct PassthruState { CCIDCardState base; CharBackend cs; uint8_t vscard_in_data[VSCARD_IN_SIZE]; uint32_t vscard_in_pos; uint32_t vscard_in_hdr; uint8_t atr[MAX_ATR_SIZE]; uint8_t atr_length; uint8_t debug; }; #define TYPE_CCID_PASSTHRU "ccid-card-passthru" DECLARE_INSTANCE_CHECKER(PassthruState, PASSTHRU_CCID_CARD, TYPE_CCID_PASSTHRU) /* * VSCard protocol over chardev * This code should not depend on the card type. */ static void ccid_card_vscard_send_msg(PassthruState *s, VSCMsgType type, uint32_t reader_id, const uint8_t *payload, uint32_t length) { VSCMsgHeader scr_msg_header; scr_msg_header.type = htonl(type); scr_msg_header.reader_id = htonl(reader_id); scr_msg_header.length = htonl(length); /* XXX this blocks entire thread. Rewrite to use * qemu_chr_fe_write and background I/O callbacks */ qemu_chr_fe_write_all(&s->cs, (uint8_t *)&scr_msg_header, sizeof(VSCMsgHeader)); qemu_chr_fe_write_all(&s->cs, payload, length); } static void ccid_card_vscard_send_apdu(PassthruState *s, const uint8_t *apdu, uint32_t length) { ccid_card_vscard_send_msg( s, VSC_APDU, VSCARD_MINIMAL_READER_ID, apdu, length); } static void ccid_card_vscard_send_error(PassthruState *s, uint32_t reader_id, VSCErrorCode code) { VSCMsgError msg = {.code = htonl(code)}; ccid_card_vscard_send_msg( s, VSC_Error, reader_id, (uint8_t *)&msg, sizeof(msg)); } static void ccid_card_vscard_send_init(PassthruState *s) { VSCMsgInit msg = { .version = htonl(VSCARD_VERSION), .magic = VSCARD_MAGIC, .capabilities = {0} }; ccid_card_vscard_send_msg(s, VSC_Init, VSCARD_UNDEFINED_READER_ID, (uint8_t *)&msg, sizeof(msg)); } static int ccid_card_vscard_can_read(void *opaque) { PassthruState *card = opaque; return VSCARD_IN_SIZE >= card->vscard_in_pos ? VSCARD_IN_SIZE - card->vscard_in_pos : 0; } static void ccid_card_vscard_handle_init( PassthruState *card, VSCMsgHeader *hdr, VSCMsgInit *init) { uint32_t *capabilities; int num_capabilities; int i; capabilities = init->capabilities; num_capabilities = 1 + ((hdr->length - sizeof(VSCMsgInit)) / sizeof(uint32_t)); init->version = ntohl(init->version); for (i = 0 ; i < num_capabilities; ++i) { capabilities[i] = ntohl(capabilities[i]); } if (init->magic != VSCARD_MAGIC) { error_report("wrong magic"); /* we can't disconnect the chardev */ } if (init->version != VSCARD_VERSION) { DPRINTF(card, D_WARN, "got version %d, have %d", init->version, VSCARD_VERSION); } /* future handling of capabilities, none exist atm */ ccid_card_vscard_send_init(card); } static int check_atr(PassthruState *card, uint8_t *data, int len) { int historical_length, opt_bytes; int td_count = 0; int td; if (len < 2) { return 0; } historical_length = data[1] & 0xf; opt_bytes = 0; if (data[0] != 0x3b && data[0] != 0x3f) { DPRINTF(card, D_WARN, "atr's T0 is 0x%X, not in {0x3b, 0x3f}\n", data[0]); return 0; } td_count = 0; td = data[1] >> 4; while (td && td_count < 2 && opt_bytes + historical_length + 2 < len) { td_count++; if (td & 0x1) { opt_bytes++; } if (td & 0x2) { opt_bytes++; } if (td & 0x4) { opt_bytes++; } if (td & 0x8) { opt_bytes++; td = data[opt_bytes + 2] >> 4; } } if (len < 2 + historical_length + opt_bytes) { DPRINTF(card, D_WARN, "atr too short: len %d, but historical_len %d, T1 0x%X\n", len, historical_length, data[1]); return 0; } if (len > 2 + historical_length + opt_bytes) { DPRINTF(card, D_WARN, "atr too long: len %d, but hist/opt %d/%d, T1 0x%X\n", len, historical_length, opt_bytes, data[1]); /* let it through */ } DPRINTF(card, D_VERBOSE, "atr passes check: %d total length, %d historical, %d optional\n", len, historical_length, opt_bytes); return 1; } static void ccid_card_vscard_handle_message(PassthruState *card, VSCMsgHeader *scr_msg_header) { uint8_t *data = (uint8_t *)&scr_msg_header[1]; switch (scr_msg_header->type) { case VSC_ATR: DPRINTF(card, D_INFO, "VSC_ATR %d\n", scr_msg_header->length); if (scr_msg_header->length > MAX_ATR_SIZE) { error_report("ATR size exceeds spec, ignoring"); ccid_card_vscard_send_error(card, scr_msg_header->reader_id, VSC_GENERAL_ERROR); break; } if (!check_atr(card, data, scr_msg_header->length)) { error_report("ATR is inconsistent, ignoring"); ccid_card_vscard_send_error(card, scr_msg_header->reader_id, VSC_GENERAL_ERROR); break; } memcpy(card->atr, data, scr_msg_header->length); card->atr_length = scr_msg_header->length; ccid_card_card_inserted(&card->base); ccid_card_vscard_send_error(card, scr_msg_header->reader_id, VSC_SUCCESS); break; case VSC_APDU: ccid_card_send_apdu_to_guest( &card->base, data, scr_msg_header->length); break; case VSC_CardRemove: DPRINTF(card, D_INFO, "VSC_CardRemove\n"); ccid_card_card_removed(&card->base); ccid_card_vscard_send_error(card, scr_msg_header->reader_id, VSC_SUCCESS); break; case VSC_Init: ccid_card_vscard_handle_init( card, scr_msg_header, (VSCMsgInit *)data); break; case VSC_Error: ccid_card_card_error(&card->base, *(uint32_t *)data); break; case VSC_ReaderAdd: if (ccid_card_ccid_attach(&card->base) < 0) { ccid_card_vscard_send_error(card, VSCARD_UNDEFINED_READER_ID, VSC_CANNOT_ADD_MORE_READERS); } else { ccid_card_vscard_send_error(card, VSCARD_MINIMAL_READER_ID, VSC_SUCCESS); } break; case VSC_ReaderRemove: ccid_card_ccid_detach(&card->base); ccid_card_vscard_send_error(card, scr_msg_header->reader_id, VSC_SUCCESS); break; default: printf("usb-ccid: chardev: unexpected message of type %X\n", scr_msg_header->type); ccid_card_vscard_send_error(card, scr_msg_header->reader_id, VSC_GENERAL_ERROR); } } static void ccid_card_vscard_drop_connection(PassthruState *card) { qemu_chr_fe_deinit(&card->cs, true); card->vscard_in_pos = card->vscard_in_hdr = 0; } static void ccid_card_vscard_read(void *opaque, const uint8_t *buf, int size) { PassthruState *card = opaque; VSCMsgHeader *hdr; if (card->vscard_in_pos + size > VSCARD_IN_SIZE) { error_report("no room for data: pos %u + size %d > %" PRId64 "." " dropping connection.", card->vscard_in_pos, size, VSCARD_IN_SIZE); ccid_card_vscard_drop_connection(card); return; } assert(card->vscard_in_pos < VSCARD_IN_SIZE); assert(card->vscard_in_hdr < VSCARD_IN_SIZE); memcpy(card->vscard_in_data + card->vscard_in_pos, buf, size); card->vscard_in_pos += size; hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr); while ((card->vscard_in_pos - card->vscard_in_hdr >= sizeof(VSCMsgHeader)) &&(card->vscard_in_pos - card->vscard_in_hdr >= sizeof(VSCMsgHeader) + ntohl(hdr->length))) { hdr->reader_id = ntohl(hdr->reader_id); hdr->length = ntohl(hdr->length); hdr->type = ntohl(hdr->type); ccid_card_vscard_handle_message(card, hdr); card->vscard_in_hdr += hdr->length + sizeof(VSCMsgHeader); hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr); } if (card->vscard_in_hdr == card->vscard_in_pos) { card->vscard_in_pos = card->vscard_in_hdr = 0; } } static void ccid_card_vscard_event(void *opaque, QEMUChrEvent event) { PassthruState *card = opaque; switch (event) { case CHR_EVENT_BREAK: card->vscard_in_pos = card->vscard_in_hdr = 0; break; case CHR_EVENT_OPENED: DPRINTF(card, D_INFO, "%s: CHR_EVENT_OPENED\n", __func__); break; case CHR_EVENT_MUX_IN: case CHR_EVENT_MUX_OUT: case CHR_EVENT_CLOSED: /* Ignore */ break; } } /* End VSCard handling */ static void passthru_apdu_from_guest( CCIDCardState *base, const uint8_t *apdu, uint32_t len) { PassthruState *card = PASSTHRU_CCID_CARD(base); if (!qemu_chr_fe_backend_connected(&card->cs)) { printf("ccid-passthru: no chardev, discarding apdu length %u\n", len); return; } ccid_card_vscard_send_apdu(card, apdu, len); } static const uint8_t *passthru_get_atr(CCIDCardState *base, uint32_t *len) { PassthruState *card = PASSTHRU_CCID_CARD(base); *len = card->atr_length; return card->atr; } static void passthru_realize(CCIDCardState *base, Error **errp) { PassthruState *card = PASSTHRU_CCID_CARD(base); card->vscard_in_pos = 0; card->vscard_in_hdr = 0; if (qemu_chr_fe_backend_connected(&card->cs)) { DPRINTF(card, D_INFO, "ccid-card-passthru: initing chardev"); qemu_chr_fe_set_handlers(&card->cs, ccid_card_vscard_can_read, ccid_card_vscard_read, ccid_card_vscard_event, NULL, card, NULL, true); ccid_card_vscard_send_init(card); } else { error_setg(errp, "missing chardev"); return; } card->debug = parse_debug_env("QEMU_CCID_PASSTHRU_DEBUG", D_VERBOSE, card->debug); assert(sizeof(DEFAULT_ATR) <= MAX_ATR_SIZE); memcpy(card->atr, DEFAULT_ATR, sizeof(DEFAULT_ATR)); card->atr_length = sizeof(DEFAULT_ATR); } static const VMStateDescription passthru_vmstate = { .name = "ccid-card-passthru", .version_id = 1, .minimum_version_id = 1, .fields = (const VMStateField[]) { VMSTATE_BUFFER(vscard_in_data, PassthruState), VMSTATE_UINT32(vscard_in_pos, PassthruState), VMSTATE_UINT32(vscard_in_hdr, PassthruState), VMSTATE_BUFFER(atr, PassthruState), VMSTATE_UINT8(atr_length, PassthruState), VMSTATE_END_OF_LIST() } }; static const Property passthru_card_properties[] = { DEFINE_PROP_CHR("chardev", PassthruState, cs), DEFINE_PROP_UINT8("debug", PassthruState, debug, 0), DEFINE_PROP_END_OF_LIST(), }; static void passthru_class_initfn(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); CCIDCardClass *cc = CCID_CARD_CLASS(klass); cc->realize = passthru_realize; cc->get_atr = passthru_get_atr; cc->apdu_from_guest = passthru_apdu_from_guest; set_bit(DEVICE_CATEGORY_INPUT, dc->categories); dc->desc = "passthrough smartcard"; dc->vmsd = &passthru_vmstate; device_class_set_props(dc, passthru_card_properties); } static const TypeInfo passthru_card_info = { .name = TYPE_CCID_PASSTHRU, .parent = TYPE_CCID_CARD, .instance_size = sizeof(PassthruState), .class_init = passthru_class_initfn, }; module_obj(TYPE_CCID_PASSTHRU); module_kconfig(USB); static void ccid_card_passthru_register_types(void) { type_register_static(&passthru_card_info); } type_init(ccid_card_passthru_register_types)