Skip to content

Latest commit

 

History

History
117 lines (78 loc) · 3.98 KB

README.md

File metadata and controls

117 lines (78 loc) · 3.98 KB
Raw

RISC-V Crypto SAIL Model

A brief explanation of the RISC-V Cryptography extension sail model, and how to patch the upstream version of SAIL with the model code in this repository.

Relevent Github issues:

A dynamically updated list can be found here. At the time of writing, these are the most relevant:

  • #20 - SAIL Support: Scalar Instructions
  • #22 - SAIL Questions.
  • #23 - Vector SHA2 Mock SAIL code
  • #24 - Vector AES Mock SAIL code

Issue #22 is used to track open questions about using SAIL, and the RISC-V implementation in SAIL.

Reading guide for the Crypto SAIL Model

  • All of the SAIL model files are found in $REPO_HOME/sail/*.sail.

    • riscv_types_crypto.sail - Common code/constants. Includes stub register access functions for the mocked vector extension.

    • riscv_insts_crypto.sail - Scalar instructions which are identical for RV32 and RV64.

    • riscv_insts_crypto_rv32.sail - RV32-only scalar instructions.

    • riscv_insts_crypto_rv64.sail - RV64-only scalar instructions.

    • riscv_insts_crypto_rvv_aes.sail - Vector AES instructions.

    • riscv_insts_crypto_rvv_alu.sail - Vector rotate, grev and carry-less multiply.

    • riscv_insts_crypto_rvv_sha.sail - Vector SHA2 instructions.

    • riscv_crypto_tests.sail - Some simple self-contained tests for the vector AES/SHA2 instructions. Very work in progress.

  • The scalar ISE code is complete (small changes or fixes not withstanding).

  • The vector ISE code is work in progress, as the base vector extension is not yet implemented in SAIL. We have tried to implement as much as possible by using stub functions for vector register get/set accesses.

Building the SAIL model.

First, you will need to build the SAIL compiler, before you can play with the RISC-V model implemented using SAIL. This process varys from platform to platform. The sail/setup-sail.sh script can be used for Ubuntu/Debian systems. See the guide from the developers of SAIL for more information.

The following commands should be executed from $REPO_HOME, having run source bin/conf.sh from the top of the riscv-crypto repository.

  • Make sure the $REPO_HOME/extern/sail-riscv git submodule is checked out.

    git submodule update --init extern/sail-riscv

  • Apply the patch to the SAIL makefile.

    make -C sail sail-apply-patch

    This applies the patch to the Makefile, and coppies the *.sail files from $REPO_HOME/sail/ to $REPO_HOME/extern/sail-riscv/model/ The *.sail sort files are not part of the patch to make it easier to manage the patch.

    Note that the SAIL model compilation process is very sensitive to file order, with non-obvious error messages or failures if something is missing, or in the wrong order.

  • Build the SAIL models:

    make -C sail/ sail-build-rv32-csim    # Build the RV32 C simulator
make -C sail/ sail-build-rv64-csim    # Build the RV64 C simulator
make -C sail/ sail-build-rv32-osim    # Build the RV32 OCaml simulator
make -C sail/ sail-build-rv64-osim    # Build the RV64 OCaml simulator
make -C sail/ sail-build-all          # Build all of the above.

    Every time one of these commands is run, the *.sail files from $REPO_HOME/sail/ are coppied to $REPO_HOME/extern/sail-riscv/model/. Hence it is these files which should be edited to make changes.

  • The SAIL repository can be put back to it's un-alterd state by running

    make -C sail sail-revert-patch

    This runs git clean under the hood.

  • Look at $REPO_HOME/tests/kat-gen for an example of running ELF files on the SAIL simulator.