Patent application number | Description | Published |
20090122980 | Cryptographic Method for Securely Implementing an Exponentiation, and an Associated Component - An asymmetrical cryptographic method applied to a message M includes a private operation of signing or decrypting the message M to obtain a signed or decrypted message s. The private operation is based on at least one modular exponentiation EM in the form EM=M | 05-14-2009 |
20090154710 | Method for the Secure Deposition of Digital Data, Associated Method for Recovering Digital Data, Associated Devices for Implementing Methods, and System Comprising Said Devices - The invention relates to a method for the secure deposition of data, according to which a depositor encrypts the data with a transfer key and encrypts the transfer key with a key of a third party, then deposits the encrypted data and the encrypted transfer key on a storage support. The invention also relates to a method for recovering data, during which an addressee of the data recovers the content of the storage support, authenticates him/herself to the third party, and transmits the encrypted transfer key thereto. After having authenticated the addressee, the third party returns the decrypted transfer key. The addressee can then recover the data. The invention further relates to devices for implementing the foregoing methods. | 06-18-2009 |
20100014656 | Cryptographic Method Comprising Secure Modular Exponentiation Against Hidden-Channel Attacks, Cryptoprocessor for Implementing the Method and Associated Chip Card - A cryptographic method carries out a modular exponentiation of the type C=A mod N, where A is an operand, B1 is a first exponent, N is a modulus and C is a result. The method includes the steps of masking the operand A by a number s, carrying out a modular exponentiation of the masked operand by the exponent B1, and de masking the result of the exponentiation, by removing a contribution from the random number s from the result of the exponentiation. During the step of masking the operand A, the operand A is multiplied by a parameter of the form K, where K is a constant and B2 is a second exponent such that B1.B2=1 mod N. The method is implemented preferably by using a Montgomery multiplier. The preferred choice for the constant K is K=2 | 01-21-2010 |
20100042851 | Method for Securely Handling Data During the Running of Cryptographic Algorithms on Embedded Systems - The invention relates to a method for handling data between two memory areas of an electronic component having at least one working memory area for carrying out operations on the component, which bring into play at least some of the data. The same memory areas are used for executing an operation, whatever the operation to be executed is, in such a manner that each operation has a hidden signal trace that is identical in terms of location leakage outside the component. | 02-18-2010 |