Move all Mifare related code from libnfc API to examples: NFC is capable of Mifare, but Mifare is not NFC.

examples/mifare.c

@@ -0,0 +1,80 @@
+#include "mifare.h"
+
+#include <string.h>
+
+#include "chips/pn53x.h"
+
+extern const byte_t pncmd_initiator_exchange_data       [265];
+
+/**
+ * @brief Execute a MIFARE Classic Command
+ * @return Returns true if action was successfully performed; otherwise returns false.
+ * @param pmp Some commands need additional information. This information should be supplied in the mifare_param union.
+ *
+ * The specified MIFARE command will be executed on the tag. There are different commands possible, they all require the destination block number.
+ * @note There are three different types of information (Authenticate, Data and Value).
+ *
+ * First an authentication must take place using Key A or B. It requires a 48 bit Key (6 bytes) and the UID. 
+ * They are both used to initialize the internal cipher-state of the PN53X chip (http://libnfc.org/hardware/pn53x-chip).
+ * After a successful authentication it will be possible to execute other commands (e.g. Read/Write). 
+ * The MIFARE Classic Specification (http://www.nxp.com/acrobat/other/identification/M001053_MF1ICS50_rev5_3.pdf) explains more about this process.
+ */
+bool nfc_initiator_mifare_cmd(const nfc_device_t* pnd, const mifare_cmd mc, const uint8_t ui8Block, mifare_param* pmp)
+{
+  byte_t abtRx[MAX_FRAME_LEN];
+  size_t szRxLen;
+  size_t szParamLen;
+  byte_t abtCmd[sizeof(pncmd_initiator_exchange_data)];
+  memcpy(abtCmd,pncmd_initiator_exchange_data,sizeof(pncmd_initiator_exchange_data));
+
+  // Make sure we are dealing with a active device
+  if (!pnd->bActive) return false;
+
+  abtCmd[2] = 0x01;     // Use first target/card
+  abtCmd[3] = mc;       // The MIFARE Classic command
+  abtCmd[4] = ui8Block; // The block address (1K=0x00..0x39, 4K=0x00..0xff)
+
+  switch (mc)
+  {
+    // Read and store command have no parameter
+    case MC_READ:
+    case MC_STORE:
+      szParamLen = 0;
+    break;
+
+    // Authenticate command
+    case MC_AUTH_A:
+    case MC_AUTH_B:
+      szParamLen = sizeof(mifare_param_auth);
+    break;
+
+    // Data command
+    case MC_WRITE:
+      szParamLen = sizeof(mifare_param_data);
+    break;
+
+    // Value command
+    case MC_DECREMENT:
+    case MC_INCREMENT:
+    case MC_TRANSFER:
+      szParamLen = sizeof(mifare_param_value);
+    break;
+
+    // Please fix your code, you never should reach this statement
+    default:
+      return false;
+    break;
+  }
+
+  // When available, copy the parameter bytes
+  if (szParamLen) memcpy(abtCmd+5,(byte_t*)pmp,szParamLen);
+
+  // Fire the mifare command
+  if (!pn53x_transceive(pnd,abtCmd,5+szParamLen,abtRx,&szRxLen)) return false;
+
+  // When we have executed a read command, copy the received bytes into the param
+  if (mc == MC_READ && szRxLen == 17) memcpy(pmp->mpd.abtData,abtRx+1,16);
+
+  // Command succesfully executed
+  return true;
+}