Patent ID: 9646306
Date: 2017-05-09
CPC Classifications: G06F,G06Q,H04L,H04W

Claim:
1. A method of safeguarding passcode entry on a mobile device, the method comprising: detecting, by the mobile device, a swipe of a financial transaction card at a card reader attached to the mobile device; initializing, by the mobile device, a financial transaction and receiving card data from the card reader attached to the mobile device; receiving, by the mobile device, a decryption-side nonce associated with the card reader; displaying, by the mobile device, a passcode entry interface on a touchscreen of the mobile device, wherein the passcode entry interface enables a user to enter a passcode; receiving, by the mobile device, the passcode entered by the user; determining, by the mobile device, a sequence of digits corresponding to the received passcode; encoding, by the mobile device, each of the determined sequence of digits into an encoded digit; encrypting, by the mobile device, the encoded digit into ciphertext using homomorphic cryptography; maintaining, by the mobile device, a cumulative product based at least partly on the ciphertexts associated with the determined sequence of digits; generating, by the mobile device, an encryption-side nonce; generating, by the mobile device, a message authentication code based at least in part on the cumulative product, the encryption-side nonce, and the decryption-side nonce; and transmitting, by the mobile device, an encrypted message including the message authentication code, wherein transmitting the encrypted message causes a process to authenticate the financial transaction to initiate, wherein the encrypted message represents the passcode entered by the user.