Cryptographic method for encrypting/decrypting an input message by means of an algorithm which admits as input data: - said input message, - a cryptographic key and - a complementary value used as a parameter of said algorithm, and as output data: the input message decrypted/encrypted by said algorithm by means of the cryptographic key and the complementary value, wherein said complementary value is determined on the basis of a unique value physically linked to an electronic device via a physically unclonable function which is inherent in this device and which is used to generate this unique value from a plurality of physical measurements (f1, f2, fn) carried out on components integrated in said device, wherein the algorithm is parameterized by the cryptographic key and also admits as input data said complementary value which is used as a second parameter of the algorithm, wherein each of said components is associated with an identifier and wherein said physically unclonable function is parameterized by a personalization data item which personalizes the electronic device during an initial configuration operation by selecting the components on which said physical measurements (f1, f2, fn) are carried out or by selecting a set of physical measurements (f1, f2, fn) according to said components, characterized in that said complementary value is a function of the result of a comparison carried out between a first data item, derived from said unique value, and a second data item used as a reference data item for checking said first data item, and characterized in that said first data item corresponds to the result of a function applied to said unique value and to the personalization data item, in that said second data item corresponds to the result of the same function applied to said expected reference value and to this same personalization data item. - said input message, - a cryptographic key and - a complementary value used as a parameter of said algorithm, and as output data: the input message decrypted/encrypted by said algorithm by means of the cryptographic key and the complementary value, wherein said complementary value is determined on the basis of a unique value physically linked to an electronic device via a physically unclonable function which is inherent in this device and which is used to generate this unique value from a plurality of physical measurements (f1, f2, fn) carried out on components integrated in said device, wherein the algorithm is parameterized by the cryptographic key and also admits as input data said complementary value which is used as a second parameter of the algorithm, wherein each of said components is associated with an identifier and wherein said physically unclonable function is parameterized by a personalization data item which personalizes the electronic device during an initial configuration operation by selecting the components on which said physical measurements (f1, f2, fn) are carried out or by selecting a set of physical measurements (f1, f2, fn) according to said components, characterized in that said complementary value is a function of the result of a comparison carried out between a first data item, derived from said unique value, and a second data item used as a reference data item for checking said first data item, and characterized in that said first data item corresponds to the result of a function applied to said unique value and to the personalization data item, in that said second data item corresponds to the result of the same function applied to said expected reference value and to this same personalization data item. the input message decrypted/encrypted by said algorithm by means of the cryptographic key and the complementary value, wherein said complementary value is determined on the basis of a unique value physically linked to an electronic device via a physically unclonable function which is inherent in this device and which is used to generate this unique value from a plurality of physical measurements (f1, f2, fn) carried out on components integrated in said device, wherein the algorithm is parameterized by the cryptographic key and also admits as input data said complementary value which is used as a second parameter of the algorithm, wherein each of said components is associated with an identifier and wherein said physically unclonable function is parameterized by a personalization data item which personalizes the electronic device during an initial configuration operation by selecting the components on which said physical measurements (f1, f2, fn) are carried out or by selecting a set of physical measurements (f1, f2, fn) according to said components, characterized in that said complementary value is a function of the result of a comparison carried out between a first data item, derived from said unique value, and a second data item used as a reference data item for checking said first data item, and characterized in that said first data item corresponds to the result of a function applied to said unique value and to the personalization data item, in that said second data item corresponds to the result of the same function applied to said expected reference value and to this same personalization data item.