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A scanner encrypts a 32 bit message 'x' using a secret 32 bit key 's1' and sends the resulting cipher y= x XOR s1 to an RFID tag. The Tag decrypts the message 'x' ,and then encrypts the message 'x' using its secret 32 bit key 's2' and sends the resulting cipher z= x XOR s2 back to the Scanner.
Assuming that I know what the hexadecimal values for the ciphers y and z are during every transmission. How can I find out what the keys s1 and s2 are using this limited information, but having access to the 'y' and 'z' values from multiple transmissions?
I understand that, because there are two different keys, but that the keys remain the same during multiple transmissions, that there is maybe some way to figure out the value of the keys.
I know that if I XOR y and z I get: 'y XOR z = s1 XOR s2'. I am not sure how to use this information or if it is relevant.
Sorry for any misused terms, I am new to cryptanalysis.