+
+/**
+ * Packs a "short" (<38-bit) HID ID from component parts.
+ *
+ * This only works with 26, 34, 35 and 37 bit card IDs.
+ *
+ * NOTE: Parity calculation is only supported on 26-bit tags. Other card lengths
+ * may have invalid parity.
+ *
+ * Returns false on invalid inputs.
+ */
+bool pack_short_hid(/* out */ uint32_t *hi, /* out */ uint32_t *lo, /* in */ const short_hid_info *info) {
+ uint32_t high = 0, low = 0;
+
+ switch (info->fmtLen) {
+ case 26: // HID H10301
+ low |= (info->cardnum & 0xffff) << 1;
+ low |= (info->fc & 0xff) << 17;
+
+ if (info->parityValid) {
+ // Calculate parity
+ low |= oddparity32((low >> 1) & 0xfff) & 1;
+ low |= (evenparity32((low >> 13) & 0xfff) & 1) << 25;
+ }
+ break;
+
+ case 34:
+ low |= (info->cardnum & 0xffff) << 1;
+ low |= (info->fc & 0x7fff) << 17;
+ high |= (info->fc & 0x8000) >> 15;
+ // TODO: Calculate parity
+ break;
+
+ case 35:
+ low |= (info->cardnum & 0xfffff) << 1;
+ low |= (info->fc & 0x7ff) << 21;
+ high |= (info->fc & 0x800) >> 11;
+ // TODO: Calculate parity
+ break;
+
+ case 37:
+ low |= (info->cardnum & 0x7ffff) << 1;
+ low |= (info->fc & 0xfff) << 20;
+ high |= (info->fc & 0xf000) >> 12;
+ // TODO: Calculate parity
+ break;
+
+ default:
+ // Invalid / unsupported length
+ return false;
+ }
+
+ // Set the highest bit
+ if (info->fmtLen != 37) {
+ // Bit 37 is always set
+ high |= 0x20;
+
+ // Set the bit corresponding to the length.
+ if (info->fmtLen < 32) {
+ low |= 1 << info->fmtLen;
+ } else {
+ high |= 1 << (info->fmtLen - 32);
+ }
+ }
+
+ // Return result only if successful.
+ *hi = high;
+ *lo = low;
+ return true;
+}
+
+
+/**
+ * Unpacks a "short" (<38-bit) HID ID into its component parts.
+ *
+ * This only works with 26, 34, 35 and 37 bit card IDs.
+ *
+ * NOTE: Parity checking is only supported on 26-bit tags.
+ *
+ * Returns false on invalid inputs.
+ */
+bool unpack_short_hid(short_hid_info *out, uint32_t hi, uint32_t lo) {
+ memset(out, 0, sizeof(short_hid_info));
+
+ if (((hi >> 5) & 1) == 1) {
+ // if bit 38 is set then < 37 bit format is used
+ uint32_t lo2 = 0;
+ // get bits 21-37 to check for format len bit
+ lo2 = (((hi & 31) << 12) | (lo >> 20));
+ uint8_t idx3 = 1;
+ // find last bit set to 1 (format len bit)
+ while (lo2 > 1) {
+ lo2 = lo2 >> 1;
+ idx3++;
+ }
+
+ out->fmtLen = idx3 + 19;
+
+ switch (out->fmtLen) {
+ case 26: // HID H10301
+ out->cardnum = (lo >> 1) & 0xFFFF;
+ out->fc = (lo >> 17) & 0xFF;
+
+ if (g_debugMode) {
+ PrintAndLog("oddparity : input=%x, calculated=%d, provided=%d",
+ (lo >> 1) & 0xFFF, oddparity32((lo >> 1) & 0xFFF), lo & 1);
+ PrintAndLog("evenparity: input=%x, calculated=%d, provided=%d",
+ (lo >> 13) & 0xFFF, evenparity32((lo >> 13) & 0xFFF) & 1, (lo >> 25) & 1);
+ }
+
+ out->parityValid =
+ (oddparity32((lo >> 1) & 0xFFF) == (lo & 1)) &&
+ ((evenparity32((lo >> 13) & 0xFFF) & 1) == ((lo >> 25) & 1));
+ break;
+
+ case 34:
+ out->cardnum = (lo >> 1) & 0xFFFF;
+ out->fc = ((hi & 1) << 15) | (lo >> 17);
+ // TODO: Calculate parity
+ break;
+
+ case 35:
+ out->cardnum = (lo >> 1) & 0xFFFFF;
+ out->fc = ((hi & 1) << 11) | (lo >> 21);
+ // TODO: Calculate parity
+ break;
+
+ default:
+ return false;
+ }
+ } else {
+ // If bit 38 is not set, then 37 bit format is used
+ out->fmtLen = 37;
+ out->cardnum = (lo >> 1) & 0x7FFFF;
+ out->fc = ((hi & 0xF) << 12) | (lo >> 20);
+ // TODO: Calculate parity
+ }
+ return true;
+}
+
+
+/**
+ * Converts a hex string to component "hi" and "lo" 32-bit integers, one nibble
+ * at a time.
+ *
+ * Returns the number of nibbles (4 bits) entered.
+ */
+int hexstring_to_int64(/* out */ uint32_t* hi, /* out */ uint32_t* lo, const char* str) {
+ // TODO: Replace this with param_gethex when it supports arbitrary length
+ // inputs.
+ int n = 0, i = 0;
+
+ while (sscanf(&str[i++], "%1x", &n ) == 1) {
+ *hi = (*hi << 4) | (*lo >> 28);
+ *lo = (*lo << 4) | (n & 0xf);
+ }
+
+ return i - 1;
+}
+
projects / proxmark3-svn / commitdiff