Tock Cryptography Working Group (crypto)

• Working Group Charter
• Adopted 09/30/2025

Goals

The goals of the Tock Working Group (crypto) are to:

• Improve and standardize HIL and system call interfaces for cryptographic primitives.
• Maintain and improve cryptography support in the Tock kernel, libtock-rs, and libtock-c.
• Review changes to the Tock kernel, libtock-rs, and libtock-c that affect cryptography support.

Members

• Tyler Potyondy (Lead), UCSD
• Hussain Miyaziwala, Microsoft/Pluton
• Kat Fox, zeroRISC
• Amit Levy (Core WG), Tock Foundation

Membership and Communication

The cryptography working group membership is open to Tock developers interested in the design of cryptography interfaces. Group membership is decided by the group: the exact process is not yet determined and may organically evolve as the group gains momentum.

The group primarily coordinates via the Cryptography WG channel in the Tock Matrix space. Those looking to engage with the working group are encouraged to join the channel.

Code Purview

The crypto working group is responsible for reviewing, approving, and merging pull requests for the following HILs:

• kernel::hil::symmetric_encryption
• kernel::hil::public_key_crypto
• kernel::hil::digest
• kernel::hil::crc
• kernel::hil::rng

capsules:

• capsules_extra::symmetric_encryption
• capsules_extra::public_key_crypto
• capsules_extra::hmac
• capsules_extra::hmac_sha256
• capsules_extra::sha
• capsules_extra::sha256
• capsules_aes_gcm
• ecdsa_sw

It will also be responsible for any additional HILs and capsules that are specific to cryptography functionality, reviewing and maintaining external dependencies on crypographic crates, as well as for reviewing, approving, and merging pull requests in libtock-c and libtock-rs that are specific to cryptography architectures, including libraries for interacting with cryptography system call drivers.

The working group's scope does not apply to subsystems that merely use cryptography interfaces.