--- /dev/null
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <stdint.h>
+#include "iso14443crc.h"
+#include "proxusb.h"
+#include "data.h"
+#include "graph.h"
+#include "ui.h"
+#include "cmdparser.h"
+#include "cmdhf14b.h"
+
+static int CmdHelp(const char *Cmd);
+
+int CmdHF14BDemod(const char *Cmd)
+{
+ int i, j, iold;
+ int isum, qsum;
+ int outOfWeakAt;
+ bool negateI, negateQ;
+
+ uint8_t data[256];
+ int dataLen = 0;
+
+ // As received, the samples are pairs, correlations against I and Q
+ // square waves. So estimate angle of initial carrier (or just
+ // quadrant, actually), and then do the demod.
+
+ // First, estimate where the tag starts modulating.
+ for (i = 0; i < GraphTraceLen; i += 2) {
+ if (abs(GraphBuffer[i]) + abs(GraphBuffer[i + 1]) > 40) {
+ break;
+ }
+ }
+ if (i >= GraphTraceLen) {
+ PrintAndLog("too weak to sync");
+ return 0;
+ }
+ PrintAndLog("out of weak at %d", i);
+ outOfWeakAt = i;
+
+ // Now, estimate the phase in the initial modulation of the tag
+ isum = 0;
+ qsum = 0;
+ for (; i < (outOfWeakAt + 16); i += 2) {
+ isum += GraphBuffer[i + 0];
+ qsum += GraphBuffer[i + 1];
+ }
+ negateI = (isum < 0);
+ negateQ = (qsum < 0);
+
+ // Turn the correlation pairs into soft decisions on the bit.
+ j = 0;
+ for (i = 0; i < GraphTraceLen / 2; i++) {
+ int si = GraphBuffer[j];
+ int sq = GraphBuffer[j + 1];
+ if (negateI) si = -si;
+ if (negateQ) sq = -sq;
+ GraphBuffer[i] = si + sq;
+ j += 2;
+ }
+ GraphTraceLen = i;
+
+ i = outOfWeakAt / 2;
+ while (GraphBuffer[i] > 0 && i < GraphTraceLen)
+ i++;
+ if (i >= GraphTraceLen) goto demodError;
+
+ iold = i;
+ while (GraphBuffer[i] < 0 && i < GraphTraceLen)
+ i++;
+ if (i >= GraphTraceLen) goto demodError;
+ if ((i - iold) > 23) goto demodError;
+
+ PrintAndLog("make it to demod loop");
+
+ for (;;) {
+ iold = i;
+ while (GraphBuffer[i] >= 0 && i < GraphTraceLen)
+ i++;
+ if (i >= GraphTraceLen) goto demodError;
+ if ((i - iold) > 6) goto demodError;
+
+ uint16_t shiftReg = 0;
+ if (i + 20 >= GraphTraceLen) goto demodError;
+
+ for (j = 0; j < 10; j++) {
+ int soft = GraphBuffer[i] + GraphBuffer[i + 1];
+
+ if (abs(soft) < (abs(isum) + abs(qsum)) / 20) {
+ PrintAndLog("weak bit");
+ }
+
+ shiftReg >>= 1;
+ if(GraphBuffer[i] + GraphBuffer[i+1] >= 0) {
+ shiftReg |= 0x200;
+ }
+
+ i+= 2;
+ }
+
+ if ((shiftReg & 0x200) && !(shiftReg & 0x001))
+ {
+ // valid data byte, start and stop bits okay
+ PrintAndLog(" %02x", (shiftReg >> 1) & 0xff);
+ data[dataLen++] = (shiftReg >> 1) & 0xff;
+ if (dataLen >= sizeof(data)) {
+ return 0;
+ }
+ } else if (shiftReg == 0x000) {
+ // this is EOF
+ break;
+ } else {
+ goto demodError;
+ }
+ }
+
+ uint8_t first, second;
+ ComputeCrc14443(CRC_14443_B, data, dataLen-2, &first, &second);
+ PrintAndLog("CRC: %02x %02x (%s)\n", first, second,
+ (first == data[dataLen-2] && second == data[dataLen-1]) ?
+ "ok" : "****FAIL****");
+
+ RepaintGraphWindow();
+ return 0;
+
+demodError:
+ PrintAndLog("demod error");
+ RepaintGraphWindow();
+ return 0;
+}
+
+int CmdHF14BList(const char *Cmd)
+{
+ uint8_t got[960];
+ GetFromBigBuf(got, sizeof(got));
+
+ PrintAndLog("recorded activity:");
+ PrintAndLog(" time :rssi: who bytes");
+ PrintAndLog("---------+----+----+-----------");
+
+ int i = 0;
+ int prev = -1;
+
+ for(;;) {
+ if(i >= 900) {
+ break;
+ }
+
+ bool isResponse;
+ int timestamp = *((uint32_t *)(got+i));
+ if(timestamp & 0x80000000) {
+ timestamp &= 0x7fffffff;
+ isResponse = 1;
+ } else {
+ isResponse = 0;
+ }
+ int metric = *((uint32_t *)(got+i+4));
+
+ int len = got[i+8];
+
+ if(len > 100) {
+ break;
+ }
+ if(i + len >= 900) {
+ break;
+ }
+
+ uint8_t *frame = (got+i+9);
+
+ char line[1000] = "";
+ int j;
+ for(j = 0; j < len; j++) {
+ sprintf(line+(j*3), "%02x ", frame[j]);
+ }
+
+ char *crc;
+ if(len > 2) {
+ uint8_t b1, b2;
+ ComputeCrc14443(CRC_14443_B, frame, len-2, &b1, &b2);
+ if(b1 != frame[len-2] || b2 != frame[len-1]) {
+ crc = "**FAIL CRC**";
+ } else {
+ crc = "";
+ }
+ } else {
+ crc = "(SHORT)";
+ }
+
+ char metricString[100];
+ if(isResponse) {
+ sprintf(metricString, "%3d", metric);
+ } else {
+ strcpy(metricString, " ");
+ }
+
+ PrintAndLog(" +%7d: %s: %s %s %s",
+ (prev < 0 ? 0 : timestamp - prev),
+ metricString,
+ (isResponse ? "TAG" : " "), line, crc);
+
+ prev = timestamp;
+ i += (len + 9);
+ }
+ return 0;
+}
+
+int CmdHF14BRead(const char *Cmd)
+{
+ UsbCommand c = {CMD_ACQUIRE_RAW_ADC_SAMPLES_ISO_14443, {strtol(Cmd, NULL, 0), 0, 0}};
+ SendCommand(&c);
+ return 0;
+}
+
+int CmdHF14Sim(const char *Cmd)
+{
+ UsbCommand c={CMD_SIMULATE_TAG_ISO_14443};
+ SendCommand(&c);
+ return 0;
+}
+
+int CmdHFSimlisten(const char *Cmd)
+{
+ UsbCommand c = {CMD_SIMULATE_TAG_HF_LISTEN};
+ SendCommand(&c);
+ return 0;
+}
+
+int CmdHF14BSnoop(const char *Cmd)
+{
+ UsbCommand c = {CMD_SNOOP_ISO_14443};
+ SendCommand(&c);
+ return 0;
+}
+
+/* New command to read the contents of a SRI512 tag
+ * SRI512 tags are ISO14443-B modulated memory tags,
+ * this command just dumps the contents of the memory
+ */
+int CmdSri512Read(const char *Cmd)
+{
+ UsbCommand c = {CMD_READ_SRI512_TAG, {strtol(Cmd, NULL, 0), 0, 0}};
+ SendCommand(&c);
+ return 0;
+}
+
+/* New command to read the contents of a SRIX4K tag
+ * SRIX4K tags are ISO14443-B modulated memory tags,
+ * this command just dumps the contents of the memory/
+ */
+int CmdSrix4kRead(const char *Cmd)
+{
+ UsbCommand c = {CMD_READ_SRIX4K_TAG, {strtol(Cmd, NULL, 0), 0, 0}};
+ SendCommand(&c);
+ return 0;
+}
+
+static command_t CommandTable[] =
+{
+ {"help", CmdHelp, 1, "This help"},
+ {"demod", CmdHF14BDemod, 1, "Demodulate ISO14443 Type B from tag"},
+ {"list", CmdHF14BList, 0, "List ISO 14443 history"},
+ {"read", CmdHF14BRead, 0, "Read HF tag (ISO 14443)"},
+ {"sim", CmdHF14Sim, 0, "Fake ISO 14443 tag"},
+ {"simlisten", CmdHFSimlisten, 0, "Get HF samples as fake tag"},
+ {"snoop", CmdHF14BSnoop, 0, "Eavesdrop ISO 14443"},
+ {"sri512read", CmdSri512Read, 0, "<int> -- Read contents of a SRI512 tag"},
+ {"srix4kread", CmdSrix4kRead, 0, "<int> -- Read contents of a SRIX4K tag"},
+ {NULL, NULL, 0, NULL}
+};
+
+int CmdHF14B(const char *Cmd)
+{
+ CmdsParse(CommandTable, Cmd);
+ return 0;
+}
+
+int CmdHelp(const char *Cmd)
+{
+ CmdsHelp(CommandTable);
+ return 0;
+}