Cryptographic Hardware 🛡️🔑

Trusted Platform Module (TPM) 🖥️🔒

• Overview:

  • A hardware device integrated into a computer to provide a dedicated crypto processor.

  • Offers secure key generation, random number generation, remote attestation, and data binding and sealing.

• Functions:

  • Hardware Authentication: Detects unauthorized hardware changes.

  • Remote Attestation: Allows a system to authenticate its software and hardware configuration to a remote system by generating a secure hash using a unique RSA key.

  • Data Binding and Sealing:

    • Data Binding: Encrypts data using a unique key derived from the TPM's secret key, binding it to the TPM and the system.

    • Data Sealing: Encrypts data with a hardware-backed key, requiring the TPM to be in a specific state for decryption.

• Implementations:

  • Discrete Chip: Most secure, includes physical tamper resistance.

  • Integrated Chip: Embedded in other chips.

  • Firmware/Software: Virtualized in a hypervisor.

Secure Elements (SE) 📱🔒

• Overview:

  • Tamper-resistant chips found in mobile devices, either embedded in the microprocessor or integrated into the main board.

  • Provides secure storage for cryptographic keys and a secure environment for applications.

• Evolution:

  • Trusted Execution Environment (TEE): An advanced secure environment running alongside the main OS, isolating applications and secure processes.

Criticism and Vulnerabilities ⚠️🔧

• Manufacturing Trust: TPMs may have their secret keys accessible to the manufacturer at the time of production, posing a potential risk.

• Physical Attacks: Advanced attacks, like those requiring electron microscopes, can potentially access TPM contents, although such attacks are highly specialized and time-consuming.

Full Disk Encryption (FDE) 💾🔒

• Concept:

  • Encrypts the entire drive, not just specific files, to protect against data theft or tampering.

  • Requires an unencrypted boot partition to load the OS and prompt for a passphrase to unlock the encrypted disk.

• Implementations:

  • PGP: Commercial product.

  • BitLocker: Microsoft's solution, integrates with TPM.

  • FileVault 2: Apple's solution.

  • dm-crypt: Open-source for Linux systems.

• Integration with TPM:

  • Uses TPM encryption keys to secure the disk and ensure platform integrity, preventing unlocking if the system configuration changes.

Random Number Generation 🎲🔢

• Importance:

  • Critical for encryption systems; non-random or predictable numbers can compromise security.

• Types:

  • True Random: Generated from unpredictable physical processes.

  • Pseudorandom: Generated algorithmically but should be seeded from a true random source.

• Entropy Pool:

  • Maintained by operating systems to seed random number generators.

  • Dedicated hardware or software generators ensure cryptographic keys are produced with high randomness.

Understanding these cryptographic hardware concepts helps in implementing robust security measures to protect data integrity and confidentiality. 🌐🔐