Merge pull request elechouse#8 from awieser/master

fixed: ndef size + possibility to set emulated tag read only
jivemonkey · Nov 22, 2013 · 07e3480 · 07e3480
2 parents fd35495 + f8b680a
commit 07e3480
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Showing 3 changed files with 42 additions and 26 deletions.
diff --git a/PN532/emulatetag.cpp b/PN532/emulatetag.cpp
@@ -48,19 +48,6 @@
 
 typedef enum { NONE, CC, NDEF } tag_file;   // CC ... Compatibility Container
 
-const uint8_t compatibility_container[] = {
-  0, 0x0F,
-  0x20,
-  0, 0x54,
-  0, 0xFF,
-  0x04,
-  0x06,
-  0xE1, 0x04,
-  0xFF, 0xFE,
-  0x00,
-  0x00
-};
-
 bool EmulateTag::init(){
   pn532.begin();
   return pn532.SAMConfig();
@@ -110,6 +97,23 @@ bool EmulateTag::emulate(const uint16_t tgInitAsTargetTimeout){
     return false;
   }
 
+  uint8_t compatibility_container[] = {
+    0, 0x0F,
+    0x20,
+    0, 0x54,
+    0, 0xFF,
+    0x04,       // T
+    0x06,       // L
+    0xE1, 0x04, // File identifier
+    ((NDEF_MAX_LENGTH & 0xFF00) >> 8), (NDEF_MAX_LENGTH & 0xFF), // maximum NDEF file size
+    0x00,       // read access 0x0 = granted
+    0x00        // write access 0x0 = granted | 0xFF = deny
+  };
+
+  if(tagWriteable == false){
+    compatibility_container[14] = 0xFF;
+  }
+
   tagWrittenByInitiator = false;
 
   uint8_t rwbuf[128];
@@ -185,13 +189,17 @@ bool EmulateTag::emulate(const uint16_t tgInitAsTargetTimeout){
       }
       break;    
     case ISO7816_UPDATE_BINARY:
-      if( p1p2_length > NDEF_MAX_LENGTH){
-	setResponse(MEMORY_FAILURE, rwbuf, &sendlen);
-      }
-      else{
-	memcpy(ndef_file + p1p2_length, rwbuf + C_APDU_DATA, lc);
-	setResponse(COMMAND_COMPLETE, rwbuf, &sendlen);
-	tagWrittenByInitiator = true;
+      if(!tagWriteable){
+	  setResponse(FUNCTION_NOT_SUPPORTED, rwbuf, &sendlen);
+      } else{      
+	if( p1p2_length > NDEF_MAX_LENGTH){
+	  setResponse(MEMORY_FAILURE, rwbuf, &sendlen);
+	}
+	else{
+	  memcpy(ndef_file + p1p2_length, rwbuf + C_APDU_DATA, lc);
+	  setResponse(COMMAND_COMPLETE, rwbuf, &sendlen);
+	  tagWrittenByInitiator = true;
+	}
       }
       break;
     default:

diff --git a/PN532/emulatetag.h b/PN532/emulatetag.h
@@ -20,7 +20,7 @@ typedef enum {COMMAND_COMPLETE, TAG_NOT_FOUND, FUNCTION_NOT_SUPPORTED, MEMORY_FA
 class EmulateTag{
 
 public:
-EmulateTag(PN532Interface &interface) : pn532(interface), uidPtr(0), tagWrittenByInitiator(false) { }
+EmulateTag(PN532Interface &interface) : pn532(interface), uidPtr(0), tagWrittenByInitiator(false), tagWriteable(true) { }
 
   bool init();
 
@@ -42,12 +42,18 @@ EmulateTag(PN532Interface &interface) : pn532(interface), uidPtr(0), tagWrittenB
     return tagWrittenByInitiator;
   }
 
+  void setTagWriteable(bool setWriteable){
+    tagWriteable = setWriteable;
+  }
+
 private:
   PN532 pn532;
   uint8_t ndef_file[NDEF_MAX_LENGTH];
   uint8_t* uidPtr;
-  void setResponse(responseCommand cmd, uint8_t* buf, uint8_t* sendlen, uint8_t sendlenOffset =0);
   bool tagWrittenByInitiator;
+  bool tagWriteable;
+
+  void setResponse(responseCommand cmd, uint8_t* buf, uint8_t* sendlen, uint8_t sendlenOffset = 0);
 };
 
 #endif
diff --git a/PN532/examples/emulate_tag_ndef/emulate_tag_ndef.ino b/PN532/examples/emulate_tag_ndef/emulate_tag_ndef.ino
@@ -46,12 +46,14 @@ void loop(){
 
     // start emulation (blocks)
     nfc.emulate();
-
+        
     // or start emulation with timeout
-
-    if(!nfc.emulate(1000)){ // timeout 1 second
+    /*if(!nfc.emulate(1000)){ // timeout 1 second
       Serial.println("timed out");
-    }
+    }*/
+
+    // deny writing to the tag
+    // nfc.setTagWriteable(false);
 
     if(nfc.writeOccured()){
        Serial.println("\nWrite occured !");