diff options
Diffstat (limited to 'hw/usb')
| -rw-r--r-- | hw/usb/ccid-card-passthru.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/hw/usb/ccid-card-passthru.c b/hw/usb/ccid-card-passthru.c index 275b8873dc..16d51c9295 100644 --- a/hw/usb/ccid-card-passthru.c +++ b/hw/usb/ccid-card-passthru.c @@ -138,6 +138,59 @@ static void ccid_card_vscard_handle_init( 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) { @@ -152,6 +205,12 @@ static void ccid_card_vscard_handle_message(PassthruState *card, 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); |