Method for validating an authentication chip
First Claim
1. A method for validating the untrusted integrated circuit, the method includes the steps of:
- generating a secret random number and calculating a signature for the random number using a signature function, in a trusted integrated circuit;
encrypting the random number and the signature using a symmetric encryption function using a first secret key, in the trusted integrated circuit;
passing the encrypted random number and signature from the trusted integrated circuit to an untrusted integrated circuit;
decrypting the encrypted random number and signature with a symmetric decryption function using the first secret key, in the untrusted integrated circuit;
calculating a signature for the decrypted random number using the signature function in the untrusted integrated circuit;
comparing the signature calculated in the untrusted integrated circuit with the signature decrypted;
in the event that the two signatures match, encrypting the decrypted random number together with a data message read from the untrusted chip by the symmetric encryption function using a second secret key and returning it together with the data message to the trusted integrated circuit;
encrypting the random number together with the data message by the symmetric encryption function using the second secret key, in the trusted integrated circuit;
comparing the two versions of the random number encrypted together with the data message using the second key, in the trusted integrated circuit;
in the event that the two versions match, considering the untrusted integrated circuit and the data message to be valid;
otherwise, considering the untrusted integrated circuit and the data message to be invalid.
3 Assignments
0 Petitions
Accused Products
Abstract
A method for validating untrusted authentication chip, the method includes the steps of: generating a secret random number and calculating a signature for the random number using a signature function, in a trusted authentication chip; encrypting the random number and the signature using a symmetric encryption function using a first secret key, in the trusted authentication chip; passing the encrypted random number and signature from the trusted authentication chip to an untrusted authentication chip; decrypting the encrypted random number and signature with a symmetric decryption function using the first secret key, in the untrusted authentication chip; calculating a signature for the decrypted random number using the signature function in the untrusted authentication chip; comparing the signature calculated in the untrusted authentication chip with the signature decrypted; in the event that the two signatures match, encrypting the decrypted random number together with a data message read from the untrusted chip by the symmetric encryption function using a second secret key and returning it together with the data message to the trusted authentication chip; encrypting the random number together with the data message by the symmetric encryption function using the second secret key, in the trusted authentication chip; comparing the two versions of the random number encrypted together with the data message using the second key, in the trusted authentication chip; in the event that the two versions match, considering the untrusted authentication chip and the data message to be valid; otherwise, considering the untrusted authentication chip and the data message to be invalid.
32 Citations
13 Claims
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1. A method for validating the untrusted integrated circuit, the method includes the steps of:
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generating a secret random number and calculating a signature for the random number using a signature function, in a trusted integrated circuit; encrypting the random number and the signature using a symmetric encryption function using a first secret key, in the trusted integrated circuit; passing the encrypted random number and signature from the trusted integrated circuit to an untrusted integrated circuit; decrypting the encrypted random number and signature with a symmetric decryption function using the first secret key, in the untrusted integrated circuit; calculating a signature for the decrypted random number using the signature function in the untrusted integrated circuit; comparing the signature calculated in the untrusted integrated circuit with the signature decrypted; in the event that the two signatures match, encrypting the decrypted random number together with a data message read from the untrusted chip by the symmetric encryption function using a second secret key and returning it together with the data message to the trusted integrated circuit; encrypting the random number together with the data message by the symmetric encryption function using the second secret key, in the trusted integrated circuit; comparing the two versions of the random number encrypted together with the data message using the second key, in the trusted integrated circuit; in the event that the two versions match, considering the untrusted integrated circuit and the data message to be valid; otherwise, considering the untrusted integrated circuit and the data message to be invalid. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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Specification