Ad-hoc trust establishment using visual verification

A method of secure key exchange comprising:

• generating at least a first key at a first device;
• transmitting a hash of at least the first key to a second device and receiving a hash of at least a second key from the second device;
• transmitting the first key to the second device and receiving the second key from the second device;
• checking that the hash of at least the second key corresponds to the second key;
• generating a visual representation of at least the first key and the second key, the generating including:
• computing a hash of at least the first key and the second key;
• dividing a predetermined number of bits of the hash into a plurality of unequal sized portions;
• mapping at least one of said plurality of portions to a graphical symbol and mapping at least another one of said plurality of portions to a background color, wherein the portion mapped to the graphical symbol comprises a larger portion than the portion mapped to the background color;
• combining at least the graphical symbol comprising the larger portion and the background color comprising the smaller portion to form the visual representation;
• creating a combination of at least the first key, the second key, and at least one of the hash of at least the first key and the hash of at least the second key;
• mapping the combination of at least the first key, the second key, and at least one of the hash of at least the first key and the hash of at least the second key to a plurality of combined graphical symbols and backgrounds;
• and
• displaying the plurality of combined graphical symbols and backgrounds as the combined visual representation.

One or more memory devices with device-executable instructions for performing steps comprising:

• generating a first public key and a corresponding private key at a first device;
• generating a first hash value from at least the first public key, the first hash value being generated from the first public key and a first value;
• sending the first hash value to a second device and receiving a second hash value from the second device, the second hash value being generated from at least a second public key;
• sending the first public key to the second device and receiving the second public key from the second device;
• verifying that the second hash value corresponds to the second public key;
• creating a combined visual representation generated from at least the first public key and the second public key, the creating including:
• computing a hash of at least the first public key and the second public key;
• dividing a predetermined number of bits of the hash into a plurality of unequal sized portions;
• mapping at least one of said plurality of portions to a first graphical feature and mapping at least another one of said plurality of portions to a second feature different from the first feature, wherein the portion mapped to the first graphical feature comprises a larger portion than the portion mapped to the second feature;
• and
• combining at least the first feature comprising the larger portion and the second feature comprising the smaller portion to form the combined visual representation;
• encrypting the first value using the second public key;
• sending the encrypted first value to the second device;
• receiving an encrypted second value from the second device;
• and
• decrypting the second encrypted value using the private key to identify a second value, the second value being used in verifying that the second hash value corresponds to the second key.