Cryptographic ASIC for key hierarchy enforcement
A cryptographic ASIC and method for enforcing a derivative key hierarchy for managing an information stream. A programming user provides a user passphrase that is used to generate a transform key and is then deleted. The transform key is inaccessibly, invisibly, and indelibly generated and stored in a one-time programmable memory with externally generated programming pulses during or after manufacture, without being reported out to the user who provided the user passphrase. A transform-enabled cryptographic circuit or method customized with the transform key processes a predetermined input message to obtain a predetermined output message indicating an identity of a particular information stream. Other input messages may also be processed, such as for verifying a blockchain, but replication requires knowledge of the transform key. Only a programming user with knowledge of the user passphrase is capable of creating an information stream, such as a blockchain.
1. A cryptographic integrated circuit for managing operations on an information stream, comprising:
a transform key generator configured to derive a transform key from a temporary copy of a user passphrase;
a one-time programmable memory configured to store the transform key using programming pulses from external circuitry, with the transform key inaccessible from outside the cryptographic integrated circuit after being stored;
a first one-way function (OWF) circuit block configured to generate a hash of an input message;
a programmable transformation function circuit block configured to be customized by the transform key and to perform a customized transformation function comprising at least one of bit inversion and bit transposition, to transform the hash of the input message into a transformed hash; and
a second OWF circuit block configured to generate a second hash of the transformed hash as an output result, wherein the information stream is a blockchain.
2. The cryptographic integrated circuit of claim 1 , wherein the transform key enables at least one of identifying the information stream and processing an input message from the information stream into the output result.
3. The cryptographic integrated circuit of claim 2 , wherein the identifying comprises generating an identifier by processing a predetermined input message.
4. The cryptographic integrated circuit of claim 1 , wherein the transform key is derived by processing the user passphrase through at least one OWF circuit block.
5. The cryptographic integrated circuit of claim 1 , wherein knowledge of the transform key enables replication of the cryptographic integrated circuit.
6. The cryptographic integrated circuit of claim 1 , wherein the user passphrase enables creation of the information stream.
7. The cryptographic integrated circuit of claim 1 , wherein the transform key is derived and stored during manufacture of the cryptographic integrated circuit.
8. The cryptographic integrated circuit of claim 1 , wherein the transform key is derived and stored after manufacture of the circuit.
9. A cryptographic method for managing operations on an information stream, the method comprising:
deriving a transform key from a temporary copy of a user passphrase;
storing the transform key in a one-time programmable memory using programming pulses from external circuitry, with the transform key inaccessible from outside the cryptographic integrated circuit after being stored;
processing an input message from the information stream by:
hashing the input message;
performing a customized transforming of the hash of the input message, with the transforming customized based on the transform key and comprising at least one of bit inversion and bit transposition, to obtain a transformed hash; and
hashing the transformed hash into an output result; and
creating the information stream based on the output result, wherein the information stream is a blockchain.
10. The cryptographic method of claim 9 , wherein the transform key is derived by processing the user passphrase through at least one one-way function (OWF).
11. The cryptographic method of claim 10 , wherein the transform key is derived from the user passphrase by a sequential application of at least two OWFs to the user passphrase.
12. The cryptographic method of claim 9 , further comprising identifying the information stream using an identifier generated by processing a predetermined input message.
13. The cryptographic method of claim 9 , wherein knowledge of the transform key enables replication of the cryptographic method.
14. The cryptographic method of claim 9 , wherein the transform key is derived and stored during manufacture of a cryptographic integrated circuit that executes the cryptographic method.
15. The cryptographic method of claim 9 , wherein the transform key is derived and stored after manufacture of a cryptographic integrated circuit that executes the cryptographic method.
16. A cryptographic system for managing operations on an information stream, the system comprising:
means for deriving a transform key from a temporary copy of a user passphrase;
means for storing the transform key in a one-time programmable memory in using programming pulses from external circuitry, with the transform key inaccessible from outside the cryptographic integrated circuit after being stored;
means for processing an input message from the information stream by hashing the input message, performing a customized transforming of the hash of the input message, with the transforming customized based on the transform key and comprising at least one of bit inversion and bit transposition, and hashing the transformed hash into an output result; and
means for creating the information stream based on the output result, wherein the information stream is a blockchain.