--- /dev/null
+//-----------------------------------------------------------------------------
+// Copyright (C) 2018 grauerfuchs
+//
+// This code is licensed to you under the terms of the GNU GPL, version 2 or,
+// at your option, any later version. See the LICENSE.txt file for the text of
+// the license.
+//-----------------------------------------------------------------------------
+// HID card format packing/unpacking support functions
+//-----------------------------------------------------------------------------
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include "hidcardformatutils.h"
+#include "ui.h"
+
+bool get_bit_by_position(/* in */hidproxmessage_t* data, /* in */uint8_t pos){
+ if (pos >= data->Length) return false;
+ pos = (data->Length - pos) - 1; // invert ordering; Indexing goes from 0 to 1. Subtract 1 for weight of bit.
+ bool result = false;
+ if (pos > 95)
+ result = false;
+ else if (pos > 63)
+ result = (data->top >> (pos - 64)) & 1;
+ else if (pos > 31)
+ result = (data->mid >> (pos - 32)) & 1;
+ else
+ result = (data->bot >> pos) & 1;
+ return result;
+}
+bool set_bit_by_position(/* inout */hidproxmessage_t* data, /* in */bool value, /* in */uint8_t pos){
+ if (pos >= data->Length) return false;
+ pos = (data->Length - pos) - 1; // invert ordering; Indexing goes from 0 to 1. Subtract 1 for weight of bit.
+ if (pos > 95) {
+ return false;
+ } else if (pos > 63) {
+ if (value)
+ data->top |= (1 << (pos - 64));
+ else
+ data->top &= ~(1 << (pos - 64));
+ return true;
+ } else if (pos > 31) {
+ if (value)
+ data->mid |= (1 << (pos - 32));
+ else
+ data->mid &= ~(1 << (pos - 32));
+ return true;
+ } else {
+ if (value)
+ data->bot |= (1 << pos);
+ else
+ data->bot &= ~(1 << pos);
+ return true;
+ }
+}
+/**
+ * Safeguard the data by doing a manual deep copy
+ *
+ * At the time of the initial writing, the struct does not contain pointers. That doesn't
+ * mean it won't eventually contain one, however. To prevent memory leaks and erroneous
+ * aliasing, perform the copy function manually instead. Hence, this function.
+ *
+ * If the definition of the hid_proxmessage struct changes, this function must also
+ * be updated to match.
+ */
+void proxmessage_datacopy(/*in*/hidproxmessage_t* src, /*out*/hidproxmessage_t* dest){
+ dest->bot = src->bot;
+ dest->mid = src->mid;
+ dest->top = src->top;
+ dest->Length = src->Length;
+}
+/**
+ *
+ * Yes, this is horribly inefficient for linear data.
+ * The current code is a temporary measure to have a working function in place
+ * until all the bugs shaken from the block/chunk version of the code.
+ *
+ */
+uint64_t get_linear_field(/* in */hidproxmessage_t* data, uint8_t firstBit, uint8_t length){
+ uint64_t result = 0;
+ for (uint8_t i = 0; i < length; i++ ) {
+ result = (result << 1) | get_bit_by_position(data, firstBit + i);
+ }
+ return result;
+}
+bool set_linear_field(/* inout */hidproxmessage_t* data, uint64_t value, uint8_t firstBit, uint8_t length){
+ hidproxmessage_t tmpdata;
+ proxmessage_datacopy(data, &tmpdata);
+ bool result = true;
+ for (int i = 0; i < length; i++){
+ result &= set_bit_by_position(&tmpdata, (value >> ((length - i) - 1)) & 1, firstBit + i);
+ }
+ if (result) proxmessage_datacopy(&tmpdata, data);
+ return result;
+}
+
+uint64_t get_nonlinear_field(/* in */hidproxmessage_t* data, uint8_t numBits, uint8_t* bits){
+ uint64_t result = 0;
+ for (int i = 0; i < numBits; i++){
+ result = (result << 1) | (get_bit_by_position(data, *(bits+i)) & 1);
+ }
+ return result;
+}
+bool set_nonlinear_field(/* inout */hidproxmessage_t* data, uint64_t value, uint8_t numBits, uint8_t* bits){
+ hidproxmessage_t tmpdata;
+ proxmessage_datacopy(data, &tmpdata);
+ bool result = true;
+ for (int i = 0; i < numBits; i++){
+ result &= set_bit_by_position(&tmpdata, (value >> ((numBits - i) - 1)) & 1, *(bits + i));
+ }
+ if (result) proxmessage_datacopy(&tmpdata, data);
+ return result;
+}
+
+uint8_t get_length_from_header(/* inout */hidproxmessage_t* data) {
+ uint8_t len = 0;
+
+ uint32_t hFmt; // for calculating card length
+ if ((data->top & 0x000FFFFF) > 0) { // > 64 bits
+ hFmt = data->top & 0x000FFFFF;
+ len = 64;
+ } else if ((data->mid & 0xFFFFFFC0) > 0) { // < 63-38 bits
+ hFmt = data->mid & 0xFFFFFFC0;
+ len = 32;
+ } else if ((data->mid & 0x00000020) == 0) { // 37 bits
+ hFmt = 0;
+ len = 37;
+ } else if ((data->mid & 0x0000001F) > 0){ // 36-32 bits
+ hFmt = data->mid & 0x0000001F;
+ len = 32;
+ } else { // <32 bits
+ hFmt = data->bot;
+ len = 0;
+ }
+
+ while (hFmt > 1) {
+ hFmt >>= 1;
+ len++;
+ }
+ return len;
+}
+
+hidproxmessage_t initialize_proxmessage_object(uint32_t top, uint32_t mid, uint32_t bot){
+ struct hidproxmessage_s result;
+ memset(&result, 0, sizeof(hidproxmessage_t));
+ result.top = top;
+ result.mid = mid;
+ result.bot = bot;
+ result.Length = get_length_from_header(&result);
+ return result;
+}
+bool add_HID_header(/* inout */hidproxmessage_t* data){
+ if (data->Length > 84 || data->Length == 0) return false; // Invalid value
+
+ if (data->Length >= 64){
+ data->top |= 1 << (data->Length - 64); // leading 1: start bit
+ data->top |= 0x09e00000; // Extended-length header
+ } else if (data->Length > 37){
+ data->mid |= 1 << (data->Length - 32); // leading 1: start bit
+ data->top |= 0x09e00000; // Extended-length header
+ } else if (data->Length == 37){
+ // No header bits added to 37-bit cards
+ } else if (data->Length >= 32){
+ data->mid |= 0x20; // Bit 37; standard header
+ data->mid |= 1 << (data->Length - 32); // leading 1: start bit
+ } else {
+ data->mid |= 0x20; // Bit 37; standard header
+ data->bot |= 1 << data->Length; // leading 1: start bit
+ }
+ return true;
+}
\ No newline at end of file
projects / proxmark3-svn / blobdiff