Method for the secure updating data areas in non volatile memory, device to perform such a method
AssigneeGemalto SA
InventorsJose Mennecart, Stephane Grellier
Life of this patent
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Abstract
The invention concerns a device to secure the data areas of a memory in an electronic component, the said component being able to modify the said data areas. The invention is characterised in that the said method includes a single backup memory of data areas including: first means of reference of the data areas to be secured, second means of backing up information on the said data areas.
Claims15
A method for updating together a plurality of data areas (Z1, Z2, . . . ) contained in a non volatile memory (EEPROM) of an electronic component, said electronic component also including a volatile memory (RAM) and a non volatile backup memory (M) comprising for each date area (Z1, Z2, . . . ):
- first means of reference (M1);
- second means of backing up information (M2);
- the method is characterized in that it includes the following steps:
- a referencing step in which a reference (1) is attributed to a data area (Z1) in the volatile memory (RAM);
- a first copying step in which said data area (Z1) and related data (L1, ADR1 . . . ) used to characterize said data area (Z1) are copied from the non volatile memory (EEPROM) to the volatile memory (RAM);
- a second copying step in which the entire content of the volatile backup memory (RAM) is copied into the non volatile backup memory (M);
- an updating step in which the content of the data area (Z1) stored in the non volatile memory (EEPROM) of the electronic component is updated;
- if there is an other data area (Z2) to update together, return to the referencing step in which a next data area (Z2) is referenced;
- if there is no other data area (Z2) to be updated together, the non volatile backup memory (M) is disabled.
A method for backing up at least one data area (Z1) contained in a non volatile memory (EEPROM) of an electronic component, said electronic component comprising a volatile memory (RAM) and a non volatile backup memory (M), the method is characterized in that it includes the following steps:
- a first copying step in which said data area (Z1) and related data (ADR1, L1, . . . ) used to characterise said data area (Z1) are copied from the non volatile memory to the volatile memory (RAM), said data area (Z1) and related data (ADR1, L1, . . . ) used to characterise said data area (Z1) constituting the entire content of the volatile backup memory (RAM);
- a second copying step in which the entire content of the volatile backup memory (RAM) is copied into the non volatile backup memory (M).
A method for restoring together a plurality of data areas (Z1, Z2, . . . ), said data areas (Z1, Z2, . . . ) being restored in a non volatile memory (EEPROM) of an electronic component and being modifiable by said electronic component, said electronic component comprising a non volatile backup memory (M), said non volatile back up memory (M) comprising for each data area (Z1):
- first means of reference (M1);
- and
- second means of backing up information (M2), said second means of backing up information (M2) comprising related data (ADR1, L1, . . . ) used to characterize said data area (Z1);
- the method being characterized in that the method comprises the following steps:
- (a) a checking step in which a first means of reference (M1) of a data area (Z1) is checked, said first means of reference (M1) is either disabled or not;
- (b) if said first means of reference (M1n) is not disabled:
- (b1) a copying step in which the data area (Z1) is copied from the non volatile backup memory (M) into the non volatile memory (EEPROM);
- and
- (b2) if there is an other data area (Z2) to be restored together, return to the checking step to check the next first means of reference (M1) of said other data area (Z2);
- (c) if the first means of reference (M1) is disabled, an disabling step in which the non volatile backup memory (M) is disabled.
A non volatile backup memory (M) comprising means of information back up (M2) related to a specific data area (Z1), characterized in said non volatile back up memory (M) also comprises means of reference (M1), each of said means of reference (M1) being associated with a specific data area (Z1) and the corresponding means of information back up (M2).
Dependencies are inferred from the claim text.