Encrypted end-to-end messaging using near-field communication (NFC) tags

A computer program product, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions readable and/or executable by a computer to cause the computer to:

• use a first symmetric key to encrypt a first private key of a first asymmetric key pair;
• store the encrypted first private key on a predetermined near-field communication (NFC) tag;
• store a first public key of the first asymmetric key pair and the first symmetric key on a predetermined central repository;
• obtain an encrypted first message and an encrypted first group key from the central repository, wherein the encrypted first message was encrypted using the first group key, wherein the encrypted first group key is the first group key encrypted using the first public key;
• use the encrypted first private key stored on the predetermined NFC tag to decrypt the encrypted first message,
• wherein using the encrypted first private key to decrypt the encrypted first message includes:
• using the first symmetric key to decrypt the encrypted first private key;
• using the first private key decrypt the encrypted first group key;
• and
• using the first group key to decrypt the encrypted first message;
• and
• store the first symmetric key to a predetermined first user device,
• wherein the first symmetric key is used to decrypt the encrypted first private key in response to a determination that the NFC tag is within a predetermined distance of the first user device.

A system,

• a processor;
• and
• logic integrated with the processor, executable by the processor, or integrated with and executable by the processor, the logic being configured to:
• use a first symmetric key to encrypt a first private key of a first asymmetric key pair,
• store the encrypted first private key on a predetermined near-field communication (NFC) tag;
• store a first public key of the first asymmetric key pair and the first symmetric key on a predetermined central repository;
• obtain an encrypted first message and an encrypted first group key from the central repository, wherein the encrypted first message was encrypted using the first group key, wherein the encrypted first group key is the first group key encrypted using the first public key;
• use the encrypted first private key stored on the predetermined NFC tag to decrypt the encrypted first message,
• wherein using the encrypted first private key to decrypt the encrypted first message includes:
• using the first symmetric key to decrypt the encrypted first private key;
• using the first private key decrypt the encrypted first group key;
• and
• using the first group key to decrypt the encrypted first message;
• and
• store the first symmetric key to a predetermined first user device,
• wherein the first symmetric key is used to decrypt the encrypted first private key in response to a determination that the NFC tag is within a predetermined distance of the first user device.