Information processing system having function of securely protecting confidential information

An information processing system comprising a first information processing apparatus and a second information processing apparatus arranged separate from said first information processing apparatus and capable of exchanging a signal with said first information processing apparatus, wherein

• said first information processing apparatus comprises
• correlation storage means for storing first encrypted information obtained by encrypting data with a first key and second encrypted information obtained by encrypting the first key with a second key, the first encrypted information being correlated with the second encrypted information;
• said second information processing apparatus comprises
• second key storage means for storing the second key, and
• first decryption means for decrypting the second encrypted information from said correlation storage means by using the second key stored in said second key storage means, thereby extracting the first key;
• and
• said first information processing apparatus further comprises second decryption means for decrypting the first encrypted information from said correlation storage means by using the first key extracted by said first decryption means, thereby obtaining the data.

An information processing apparatus comprising:

• first key generation means for generating a first key;
• encryption means for encrypting data with the first key generated by said first key generation means;
• input means for outputting the first key generated by said first key generation means to an external information processing apparatus and inputting, in said external information processing apparatus, the first key encrypted with a second key stored in said external information processing apparatus;
• and
• storage means for storing the encrypted first key input through said input means and the data encrypted by said encryption means, the encrypted first key being correlated with the encrypted data.

An information processing apparatus comprising:

• storage means for storing first encrypted information obtained by encrypting data with a first key and second encrypted information obtained by encrypting the first key with a second key;
• input means for outputting the second encrypted information from said storage means to an external information processing apparatus, and inputting a decrypted first key obtained by decrypting, in said external information processing apparatus, the second encrypted information with the second key stored in said external information processing apparatus;
• and
• decryption means for decrypting the first encrypted information with the decrypted first key input through said input means, thereby obtaining the data.

An information processing apparatus comprising:

• storage means for storing a second key;
• input means for inputting the first key from an external information processing apparatus which encrypts data with the first key;
• encryption means for encrypting the first key input through said input means, by using the second key stored in said storage means;
• and
• output means for outputting the encrypted first key to said external information processing apparatus so as to store the first key encrypted by said encryption means and the encrypted data in correlation with the encrypted first key in said external information processing apparatus.

An information processing apparatus comprising:

• second key storage means for storing a second key;
• input means for inputting second encrypted information from an external information processing apparatus having storage means for storing first encrypted information obtained by encrypting data with a first key and the second encrypted information obtained by encrypting the first key with the second key stored in said second key storage means;
• decryption means for decrypting with the second key the second encrypted information input through said input means to extract the first key;
• and
• output means for outputting the extracted first key to said external information processing apparatus in order to decrypt the first encrypted information with the first key extracted by said decryption means to obtain the data.

An information processing method comprising:

• the first key generation step of generating a first key in a first information processing apparatus;
• the first encrypted information generation step of encrypting data using the generated first key to generate first encrypted information;
• the output step of outputting the first key to a second information processing apparatus which is arranged separate from said first information processing apparatus and stores a second key;
• the second encrypted information generation step of encrypting the first key using the second key in said second information processing apparatus to generate second encrypted information;
• the output step of outputting the generated second encrypted information to said first information processing apparatus;
• and
• the storage step of storing the first encrypted information and the second encrypted information in correlation with the first encrypted information in said first information processing apparatus.

An information processing method comprising:

• the output step of outputting second encrypted information from a first information processing apparatus to a second information processing apparatus separate from said first information processing apparatus, said first information processing apparatus storing first encrypted information obtained by encrypting data with a first key and the second encrypted information obtained by encrypting the first key with a second key, and the first encrypted information being correlated with the second encrypted information;
• the first key extraction step of decrypting the second encrypted information with the second key stored in said second information processing apparatus in advance to extract the first key;
• the output step of outputting the extracted first key to said first information processing apparatus;
• and
• the data acquisition step of decrypting the first encrypted information with the first key in said first information processing apparatus to obtain the data.

An information processing method comprising:

• the first key generation step of generating a first key;
• the encryption step of encrypting data with the generated first key;
• the output step of outputting the generated first key to an external information processing apparatus;
• the input step of inputting, in said external information processing apparatus, the first key encrypted with the second key stored in said external information processing apparatus;
• and
• the storage step of storing the input encrypted first key and data encrypted with the first key, the encrypted first key being correlated with the encrypted data.

An information processing method comprising:

• the output step of outputting, to an external information processing apparatus, second encrypted information of first encrypted information stored and obtained by encrypting data with a first key and the second encrypted information stored and obtained by encrypting the first key with a second key;
• the input step of inputting, in said external information processing apparatus, the first key obtained by decrypting the second encrypted information with the second key stored in said external information processing apparatus;
• and
• the extraction step of decrypting the first encrypted information with the input first key to extract the data.

An information processing method comprising:

• the input step of inputting a generated first key from an external information processing apparatus which encrypts data with the first key;
• the encryption step of encrypting the input first key with a second key stored in advance;
• and
• the output step of outputting the encrypted first key to said external information processing apparatus in order to store the encrypted first key and the encrypted data in correlation with the encrypted first key in said external information processing apparatus.

An information processing method comprising:

• the input step of inputting second encrypted information form an external information processing apparatus having storage means for storing first encrypted information obtained by encrypting data with a first key and the second encrypted information obtained by encrypting the first key with a second key;
• the extraction step of decrypting the second encrypted information with the second key stored in advance to extract the first key;
• and
• the output step of outputting the decrypted extracted first key to said external information processing apparatus in order to decrypt the first encrypted information with the extracted first key to obtain the data in said external information processing apparatus.

A program storage device which stores a program readable from a machine in order to execute method steps for performing encryption processing, wherein the method steps comprise:

• the first key generation step of generating a first key;
• the encryption step of encrypting data with the generated first key;
• the output step of outputting the generated first key to an external information processing apparatus;
• the input step of inputting, in said external information processing apparatus, the first key encrypted with a second key stored in said external information processing apparatus;
• and
• the storage step of storing the encrypted input first key and the data encrypted with the first key, the encrypted input first key being correlated with the data encrypted with the first key.

A program storage device which stores a program readable from a machine in order to execute method steps for performing encryption processing, wherein the method steps comprise:

• the output step of outputting, to an external information processing apparatus, second encrypted information of first encrypted information stored and obtained by encrypting data with a first key and the second encrypted information stored and obtained by encrypting the first key with a second key;
• the input step of inputting, in said external information processing apparatus, the first key obtained by decrypting the second encrypted information with the second key stored in said external information processing apparatus;
• and
• the extraction step of decrypting the first encrypted information with the input first key to extract the data.

A key determination method for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a second key corresponding to a specific key of the receiving side, the method comprising steps of:

• inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the second key corresponding to the specific key of the receiving side;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the second key;
• executing a second processing including the first processing on the plurality of first data, the second data, and the specific key of the receiving side, to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the second key corresponding to the specific key of the receiving side;
• and
• outputting the first key obtained from the determined one of the plurality of first data by using the specific key.

A key determination method for determining, at a receiving side, which one of a plurality of second keys of the receiving side corresponds to a specific key of the transmitting side, the specific key having been used in obtaining first data at a transmitting side to encrypt/decrypt a first key, the method comprising steps of:

• inputting the first data from the transmitting side, the first data having been obtained at the transmitting side by encrypting/decrypting the first key using the specific key of the transmitting side;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the specific key;
• executing a second processing including the first processing on the first data, the second data, and the plurality of second keys of the receiving side, to determine which one of the plurality of second keys corresponds to the specific key of the transmitting side used in obtaining the first data;
• and
• outputting the first key obtained from the first data by using the determined one of the plurality of second keys.

A key determination method for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a specific second key, the method comprising steps of:

• inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the specific second key;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by encrypting/decrypting the first key using the first key;
• executing a processing on the plurality of first data and the second data using the specific key to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the specific second key;
• and
• outputting the first key obtained by the processing using the specific second key from the determined one of the plurality of first data.

A key determination apparatus for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a second key corresponding to a specific key of the receiving side, the apparatus comprising:

• first input means for inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the second key corresponding to the specific key of the receiving side;
• second input means for inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the second key;
• execution means for executing a second processing including the first processing on the plurality of first data, the second data, and the specific key of the receiving side, to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the second key corresponding to the specific key of the receiving side;
• and
• output means for outputting the first key obtained from the determined one of the plurality of first data by using the specific key.

A key determination apparatus for determining, at a receiving side, which one of a plurality of second keys of the receiving side corresponds to a specific key of the transmitting side, the specific key having been used in obtaining first data at a transmitting side to encrypt/decrypt a first key, the apparatus comprising:

• first input means for inputting the first data from the transmitting side, the second having been obtained at the transmitting side by encrypting/decrypting the first key using the specific key of the transmitting side;
• second input means for inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the specific key;
• execution means for executing a second processing including the first processing on the first data, the second data, and the plurality of second keys of the receiving side, to determine which one of the plurality of second keys corresponds to the specific key of the transmitting side used in obtaining the first data;
• and
• output means for outputting the first key obtained from the first data by using the determined one of the plurality of second keys.

A key determination apparatus for determining at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a specific key, the apparatus comprising:

• first input means for inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the specific second key;
• second input means for inputting second data from the transmitting side, the second data having been obtained at the transmitting side by encrypting/decrypting the first key using the first key;
• execution means for executing a processing on the plurality of first data and the second data using the specific key to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the specific second key;
• and
• output means for outputting the first key obtained by the processing using the specific second key from the determined one of the plurality of first data.

A program storage device which stores a program readable from a machine in order to execute a key determination step for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a specific key corresponding to a specific key of the receiving side, the key determination step comprising the steps of:

• inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the second key corresponding to the specific key of the receiving side;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the second key;
• executing a second processing including the first processing on the plurality of first data, the second data, and the specific key of the receiving side, to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the second key corresponding to the specific key of the receiving side;
• and
• outputting the first key obtained from the determined one of the plurality of first data by using the specific key.

A program storage medium which stores a program readable from a machine in order to execute a key determination step for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a specific key corresponding to a specific key of the receiving side, the key determination step comprising the steps of:

• inputting the first data from the transmitting side, the first data having been obtained at the transmitting side by encrypting/decrypting the first key using the specific key of the transmitting side;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the specific key;
• executing a second processing including the first processing on the first data, the second data, and the plurality of second keys of the receiving side, to determine which one of the plurality of second keys corresponds to the specific key of the transmitting side used in obtaining the first data;
• and
• outputting the first key obtained from the first data by using the determined one of the plurality of second keys.

A program storage medium which stores a program readable from a machine in order to execute a key determination step for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a specific key corresponding to a specific key of the receiving side, the key determination step comprising the steps of:

• inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the specific second key;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by encrypting/decrypting the first key using the first key;
• executing a processing on the plurality of first data and the second data using the specific key to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the specific second key;
• and
• outputting the first key obtained by the processing using the specific second key from the determined one of the plurality of first data.

A key determination method for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a second key corresponding to a specific key of the receiving side, the method comprising steps of:

• inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the second key corresponding to the specific key of the receiving side;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the second key;
• executing a second processing opposite to that of the first processing on the plurality of first data, the second data, and the specific key of the receiving side, to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the second key corresponding to the specific key of the receiving side;
• and
• outputting the first key obtained from the determined one of the plurality of first data by using the specific key.

A key determination method for determining, at a receiving side, which one of a plurality of second keys of the receiving side corresponds to a specific key of the transmitting side, the specific key having been used in obtaining first data at a transmitting side to encrypt/decrypt a first key, the method comprising steps of:

• inputting the first data from the transmitting side, the first data having been obtained at the transmitting side by encrypting/decrypting the first key using the specific key of the transmitting side;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the specific key;
• executing a second processing opposite to that of the first processing on the first data, the second data, and the plurality of second keys of the receiving side, to determine which one of the plurality of second keys corresponds to the specific key of the transmitting side used in obtaining the first data;
• and
• outputting the first key obtained from the first data by using the determined one of the plurality of second keys.

A key determination apparatus for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a second key corresponding to a specific key of the receiving side, the apparatus comprising:

• first input means for inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the second key corresponding to the specific key of the receiving side;
• second input means for inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the second key;
• execution means for executing a second processing opposite to that of the first processing on the plurality of first data, the second data, and the specific key of the receiving side, to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the second key corresponding to the specific key of the receiving side;
• and
• output means for outputting the first key obtained from the determined one of the plurality of first data by using the specific key.

A key determination apparatus for determining, at a receiving side, which one of a plurality of second keys of the receiving side corresponds to a specific key of the transmitting side, the specific key having been used in obtaining first data at a transmitting side to encrypt/decrypt a first key, the apparatus comprising:

• first input means for inputting the first data from the transmitting side, the first data having been obtained at the transmitting side by encrypting/decrypting the first key using the specific key of the transmitting side;
• second input means for inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the specific key;
• execution means for executing a second processing opposite to that of the first processing on the first data, the second data, and the plurality of second keys of the receiving side, to determine which one of the plurality of second keys corresponds to the specific key of the transmitting side used in obtaining the first data;
• and
• output means for outputting the first key obtained from the first data by using the determined one of the plurality of second keys.

A program storage device which stores a program readable from a machine in order to execute a key determination step for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a specific key corresponding to a specific key of the receiving side, the key determination step comprising the steps of:

• inputting the plurality of first data, each first data having been obtained at the transmitting side by encrypting/decrypting the first key using each one of a plurality of second keys, the plurality of second keys including the second key corresponding to the specific key of the receiving side;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the second key;
• executing a second processing opposite to that of the first processing on the plurality of first data, the second data, and the specific key of the receiving side, to determine which one of the plurality of first data has been obtained by encrypting/decrypting the first key using the second key corresponding to the specific key of the receiving side;
• and
• outputting the first key obtained from the determined one of the plurality of first data by using the specific key.

A program storage medium which stores a program readable from a machine in order to execute a key determination step for determining, at a receiving side, which one of a plurality of first data received from a transmitting side has been obtained by encrypting/decrypting a first key using a specific key corresponding to a specific key of the receiving side, the key determination step comprising the steps of:

• inputting the first data from the transmitting side, the first data having been obtained at the transmitting side by encrypting/decrypting the first key using the specific key of the transmitting side;
• inputting second data from the transmitting side, the second data having been obtained at the transmitting side by executing a first processing on at least one of the first key and the specific key;
• executing a second processing opposite to that of the first processing on the first data, the second data, and the plurality of second keys of the receiving side, to determine which one of the plurality of second keys corresponds to the specific key of the transmitting side used in obtaining the first data;
• and
• outputting the first key obtained from the first data by using the determined one of the plurality of second keys.