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US 8,788,847 B2Granted
Secure data processing method and associated device
AssigneeOberthur Technologies
InventorsHugues Thiebeauld De La Crouee, Christophe Giraud
Life of this patent
Estimating the term…
Abstract
A secure data processing method includes the following steps: padding (E206) a memory area (MAC′) with a pad value (A); writing (E208) a first datum in the memory area (MAC′); in the area, reading (E210) a second datum with at least one part of the first datum as it was written in the memory area (MAC′); and executing an operation (E210) using the second datum.
Claims15
A secure data processing method that is executed by a microcircuit card and a host external to the microcircuit card, comprising:
- in the microcircuit card, filling an area of a volatile memory with a filling value;
- in the microcircuit card, reading a first data item from a non-volatile memory;
- in the microcircuit card, transmitting the first data item to a host device;
- in the microcircuit card, writing the first data item into said area of the volatile memory to replace said filling value;
- in the microcircuit card, reading from said area of the volatile memory a second data item that repeats at least a portion of the first data item as written in said area;
- in the microcircuit card, executing an operation using the second data item to produce a second data item;
- in the host, executing an operation using the
- first data item received from the microcircuit card to produce a third data item;
- in the microcircuit card, receiving the third data item from the host device;
- and
- in the microcircuit card, comparing the second data item to the third data item;
- and
- in the microcircuit card, executing a protected operation if and only if the comparing step determines a positive match between the second data item and the third data item.
10 more elements
A method of securing a protected operation of a first device, said first device being a microcircuit device and configured for communication with a second device external to the first device, comprising:
- in the first device, transmitting a data item to the second device;
- in the first device, filling an area of volatile memory with a filling value;
- in the first device, reading a first data item from a non-volatile memory;
- in the first device, writing into said area of the volatile memory the first data item, thus replacing said filling value and conditioning a future execution of the protected operation;
- in the first device, reading from said area of the volatile memory a second data item that repeats at least a portion of the first data item as written in said area;
- in the first device, executing an operation using the second data item to produce a second data item;
- in the second device, executing an operation using
- the first data item received from the first device to produce a third data item;
- in the first device, receiving the third data item from the second device;
- and
- in the first device, comparing the second data item to the third data item;
- and
- in the first device, executing a protected operation
- if and only if the comparing step determines a positive
- match between the second data item and the third data item.
12 more elements
A secure data processing device, comprising:
- a microprocessor programmed to perform, via implementation in a microcircuit card each of the steps of:
- filling an area of volatile memory with a filling value;
- reading a first data item from a non-volatile memory;
- transmitting the first data item to a host device;
- writing the first data item into said area such to replace said filling value in said area;
- reading in said area a second data item comprising at least a portion of the first data item as written in said area;
- receiving a third data item from the host device, said third data item being the result of an operation performed on the first data item that was received from the microcircuit card;
- comparing the second data item to the third data item;
- and
- executing an operation using the second data item if and only if the comparing step determines a positive match between the second data item and the third data item.
7 more elements
A protected operation execution securing device, comprising:
- a microprocessor programmed to perform, via implementation in a microcircuit card each of the steps of:
- filling an area of volatile memory with a filling value;
- reading a first data item from a non-volatile memory;
- transmitting the first data item to a host device;
- writing in said area the first data item, thereby replacing said filling value in said area for conditioning a future execution of the protected operation;
- reading in said area a second data item comprising at least a portion of the first data item as written in said area;
- receiving a third data item from the host device, said third data item being the result of an operation performed on the first data item received by the host device from the microcircuit card;
- comparing the second data item to the third data item.
5 more elements
Dependencies are inferred from the claim text.