#define GSCIS_TAG_CERTIFICATE         0x70
#define GSCIS_TAG_CERT_ISSUE_DATE     0x71
#define GSCIS_TAG_CERT_EXPIRE_DATE    0x72

/** Applet IDs **/
#define GSCIS_AID_CCC                 0xA0, 0x00, 0x00, 0x01, 0x16, 0xDB, 0x00

/* Maximum size of data portion of APDUs */
/* Do not set this above 252 */
#define CACKEY_APDU_MTU               128
/** Do not set this above 250 **/
#define CACKEY_APDU_MTU               250

#ifdef CACKEY_DEBUG

#  define CACKEY_DEBUG_PRINTF(x...) { fprintf(stderr, "%s():%i: ", __func__, __LINE__); fprintf(stderr, x); fprintf(stderr, "\n"); fflush(stderr); }
#  define CACKEY_DEBUG_PRINTBUF(f, x, y) { unsigned char *TMPBUF; unsigned long idx; TMPBUF = (unsigned char *) (x); fprintf(stderr, "%s():%i: %s  (%s/%lu = {%02x", __func__, __LINE__, f, #x, (unsigned long) (y), TMPBUF[0]); for (idx = 1; idx < (y); idx++) { fprintf(stderr, ", %02x", TMPBUF[idx]); }; fprintf(stderr, "})\n"); fflush(stderr); }
#  define CACKEY_DEBUG_PERROR(x) { fprintf(stderr, "%s():%i: ", __func__, __LINE__); perror(x); fflush(stderr); }
#  define free(x) { CACKEY_DEBUG_PRINTF("FREE(%p) (%s)", x, #x); free(x); }

		CACKEY_DEBUG_PRINTF("Sending APDU: <<censored>>");
	} else {
		CACKEY_DEBUG_PRINTBUF("Sending APDU:", xmit_buf, xmit_len);
	}

	recv_len = sizeof(recv_buf);
	scard_xmit_ret = SCardTransmit(slot->pcsc_card, SCARD_PCI_T0, xmit_buf, xmit_len, SCARD_PCI_T1, recv_buf, &recv_len);
	if (scard_xmit_ret == SCARD_E_NOT_TRANSACTED) {
		CACKEY_DEBUG_PRINTF("Failed to send APDU to card (SCardTransmit() = SCARD_E_NOT_TRANSACTED), retrying...");

		recv_len = sizeof(recv_buf);
		scard_xmit_ret = SCardTransmit(slot->pcsc_card, SCARD_PCI_T0, xmit_buf, xmit_len, SCARD_PCI_T1, recv_buf, &recv_len);
	}
	if (scard_xmit_ret != SCARD_S_SUCCESS) {
		CACKEY_DEBUG_PRINTF("Failed to send APDU to card (SCardTransmit() = %s/%lx)", CACKEY_DEBUG_FUNC_SCARDERR_TO_STR(scard_xmit_ret), (unsigned long) scard_xmit_ret);
		CACKEY_DEBUG_PRINTF("Marking slot as having been reset");

		slot->transaction_depth = 0;
		slot->slot_reset = 1;