rfid_default_keys check with RC522

I just received a RC522 board and since i am new to RFID, I tried out some examples from "Arduino RFID Library for MFRC522". Here's one of them rfid_default_keys

/*
 * ----------------------------------------------------------------------------
 * This is a MFRC522 library example; see https://github.com/miguelbalboa/rfid
 * for further details and other examples.
 * 
 * NOTE: The library file MFRC522.h has a lot of useful info. Please read it.
 * 
 * Released into the public domain.
 * ----------------------------------------------------------------------------
 * Example sketch/program which will try the most used default keys listed in 
 * https://code.google.com/p/mfcuk/wiki/MifareClassicDefaultKeys to dump the
 * block 0 of a MIFARE RFID card using a RFID-RC522 reader.
 * 
 * Typical pin layout used:
 * -----------------------------------------------------------------------------------------
 * MFRC522 Arduino Arduino Arduino Arduino Arduino
 * Reader/PCD Uno Mega Nano v3 Leonardo/Micro Pro Micro
 * Signal Pin Pin Pin Pin Pin Pin
 * -----------------------------------------------------------------------------------------
 * RST/Reset RST 9 5 D9 RESET/ICSP-5 RST
 * SPI SS SDA(SS) 10 53 D10 10 10
 * SPI MOSI MOSI 11 / ICSP-4 51 D11 ICSP-4 16
 * SPI MISO MISO 12 / ICSP-1 50 D12 ICSP-1 14
 * SPI SCK SCK 13 / ICSP-3 52 D13 ICSP-3 15
 *
 */
#include <SPI.h>
#include <MFRC522.h>
#define RST_PIN 9 // Configurable, see typical pin layout above
#define SS_PIN 10 // Configurable, see typical pin layout above
MFRC522 mfrc522(SS_PIN, RST_PIN); // Create MFRC522 instance.
// Number of known default keys (hard-coded)
// NOTE: Synchronize the NR_KNOWN_KEYS define with the defaultKeys[] array
#define NR_KNOWN_KEYS 8
// Known keys, see: https://code.google.com/p/mfcuk/wiki/MifareClassicDefaultKeys
byte knownKeys[NR_KNOWN_KEYS][MFRC522::MF_KEY_SIZE] = {
 {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}, // FF FF FF FF FF FF = factory default
 {0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5}, // A0 A1 A2 A3 A4 A5
 {0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5}, // B0 B1 B2 B3 B4 B5
 {0x4d, 0x3a, 0x99, 0xc3, 0x51, 0xdd}, // 4D 3A 99 C3 51 DD
 {0x1a, 0x98, 0x2c, 0x7e, 0x45, 0x9a}, // 1A 98 2C 7E 45 9A
 {0xd3, 0xf7, 0xd3, 0xf7, 0xd3, 0xf7}, // D3 F7 D3 F7 D3 F7
 {0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff}, // AA BB CC DD EE FF
 {0x00, 0x00, 0x00, 0x00, 0x00, 0x00} // 00 00 00 00 00 00
};
/*
 * Initialize.
 */
void setup() {
 Serial.begin(9600); // Initialize serial communications with the PC
 while (!Serial); // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)
 SPI.begin(); // Init SPI bus
 mfrc522.PCD_Init(); // Init MFRC522 card
 Serial.println(F("Try the most used default keys to print block 0 of a MIFARE PICC."));
}
/*
 * Helper routine to dump a byte array as hex values to Serial.
 */
void dump_byte_array(byte *buffer, byte bufferSize) {
 for (byte i = 0; i < bufferSize; i++) {
 Serial.print(buffer[i] < 0x10 ? " 0" : " ");
 Serial.print(buffer[i], HEX);
 }
}
/*
 * Try using the PICC (the tag/card) with the given key to access block 0.
 * On success, it will show the key details, and dump the block data on Serial.
 *
 * @return true when the given key worked, false otherwise.
 */
boolean try_key(MFRC522::MIFARE_Key *key)
{
 boolean result = false;
 byte buffer[18];
 byte block = 0;
 byte status;
 // Serial.println(F("Authenticating using key A..."));
 status = mfrc522.PCD_Authenticate(MFRC522::PICC_CMD_MF_AUTH_KEY_A, block, key, &(mfrc522.uid));
 if (status != MFRC522::STATUS_OK) {
 // Serial.print(F("PCD_Authenticate() failed: "));
 // Serial.println(mfrc522.GetStatusCodeName(status));
 return false;
 }
 // Read block
 byte byteCount = sizeof(buffer);
 status = mfrc522.MIFARE_Read(block, buffer, &byteCount);
 if (status != MFRC522::STATUS_OK) {
 // Serial.print(F("MIFARE_Read() failed: "));
 // Serial.println(mfrc522.GetStatusCodeName(status));
 }
 else {
 // Successful read
 result = true;
 Serial.print(F("Success with key:"));
 dump_byte_array((*key).keyByte, MFRC522::MF_KEY_SIZE);
 Serial.println();
 // Dump block data
 Serial.print(F("Block ")); Serial.print(block); Serial.print(F(":"));
 dump_byte_array(buffer, 16);
 Serial.println();
 }
 Serial.println();
 mfrc522.PICC_HaltA(); // Halt PICC
 mfrc522.PCD_StopCrypto1(); // Stop encryption on PCD
 return result;
}
/*
 * Main loop.
 */
void loop() {
 // Look for new cards
 if ( ! mfrc522.PICC_IsNewCardPresent())
 return;
 // Select one of the cards
 if ( ! mfrc522.PICC_ReadCardSerial())
 return;
 // Show some details of the PICC (that is: the tag/card)
 Serial.print(F("Card UID:"));
 dump_byte_array(mfrc522.uid.uidByte, mfrc522.uid.size);
 Serial.println();
 Serial.print(F("PICC type: "));
 byte piccType = mfrc522.PICC_GetType(mfrc522.uid.sak);
 Serial.println(mfrc522.PICC_GetTypeName(piccType));
 // Try the known default keys
 MFRC522::MIFARE_Key key;
 for (byte k = 0; k < NR_KNOWN_KEYS; k++) {
 // Copy the known key into the MIFARE_Key structure
 for (byte i = 0; i < MFRC522::MF_KEY_SIZE; i++) {
 key.keyByte[i] = knownKeys[k][i];
 }
 // Try the key
 if (try_key(&key)) {
 // Found and reported on the key and block,
 // no need to try other keys for this PICC
 break;
 }
 }
}

So i modified the code to see exactly what is happening there and here is my output: my output

Everything looks fine, right ? So i tried to modify it again by adding some more stuff to the knownKeys array but it looks like that only the first key is used in the actual authentication. Here's an output for the same card but i moved {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}, // FF FF FF FF FF FF = factory default to the end of that array. enter image description here

So.. as you can see even if it used the right key, nothing happened. For the solution i tried few things but without a success. Thanks in advance for answering.

4 Answers 4

Start asking to get answers

Find the answer to your question by asking.

Explore related questions

See similar questions with these tags.