Status at a glance:
- Current Definition-of-Done Status: Stable
- Next Definition-of-Done Status:: Freeze
- (allows start of formal public review period)
- Definition of Done Status Top Sheet
Scalar Crypto Specification:
- Latest Draft Scalar Crypto Specification (v0.9.4)
- Contains updates from the architectural review (30/June/2021).
Lightweight instruction set extensions for RV32 and RV64 HARTs. Proposed extensions:
- Extensions fully defined in the Scalar Crypto Specification: Zk, Zkn, Zks, Zkr, Zkne, Zknd, Zknh, Zksed, Zksh, Zkt
- Shared with the Bit-Manipulation Specification: Zbkx, Zbkc, Zbkb
- Instruction Group Names Diagram (click thumbnail for full-size image)
Architecture & Opcode consistency review
- The results of the review can be seen here. Scalar Crypto Arch Review Results.pdf
- After discussion within the task group, the following changes will be made to the spec, with the changes expected to land in 0.9.4 before the end of August.
- Stop overlapping the aes32 and aes64 opcodes. See riscv/riscv-opcodes#77
- Clarify the effect of misa.k
- Some updates to the entropy source and zkt detailed here.
- Miscellaneous editorial issues.
- Some downstream tasks for our group development partners once 0.9.4 lands:
| Who | What | Status | Task |
|---|---|---|---|
| PLCT | GCC | Not started | Update extension names: Zkb → Zbkb etc. |
| PLCT | LLVM | Not started | Update aes32/64* encodings if applicable. |
| PLCT | GCC | Not started | Update extension names: Zkb → Zbkb etc. |
| PLCT | LLCM | Not started | Update aes32/64* encodings if applicable. |
| IIT | riscv-config | Not started | Update extension names: Zkb → Zbkb etc. |
| IIT | riscv-config | Not started | Update instruction inclusion in different extensions |
| IIT | riscv-arch-tests | Not started | Break up K suite into Zk* extensions |
| IIT | riscv-arch-tests | Not started | Update instruction inclusion in different extensions |
Architecture Tests
- Test plan for the scalar-crypto specific instructions is available.
- Imperas have a complete set of tests, written to the existing test plan, for the scalar crypto instructions and the bitmanip instructions we borrow.
- These have been merged into the main test suite as of PR#177, with many thanks to Imperas for the contribution.
- Spike, OVPSim and Sail all agree on the test signatures.
- They form a base we can use to develop prototype implementations / Spike / SAIL / QEMU very easily and quickly.
- These have been merged into the main test suite as of PR#177, with many thanks to Imperas for the contribution.
- Upstream Spike support for enabling it to work with the K test suite is being added in PR#687.
- IIT Madras are also looking at writing the scalar crypto tests for integration into the official architectural tests repo as well.
- Agreed SoW for IITM
- They are re-implementing the tests as part of the blessed coverage and test generation tooling.
- Making good progress with the simple test patterns for scalar-crypto specific instructions A/O April 7'th '21
- We then switch over to using the IIT tests when they are finished, since they will be easier to maintain/extend going forward than the Imperas tests.
- YAML config changes for K have been merged in. See here.
- Status from IIT Madras as on 17-Jun:
- All test cases and coverage reports has been generated and presented.
- If there are any changes in future on these that is required in future, IIT Madras will enhance the scripts as per requirements.
- Status from IIT Madras as on 20-May:
- Real world test cases as per the test plan has been generated.
- Currently waiting for the fixed toolchain with K extension from PLCT to test the generated test cases. All the test cases are working fine when we run against the patched toolchain
- A PR has been raised with a pull request for this suite to be reviewed and merged in the riscv-arch tests github repo.
- Status from IIT Madras as on 12-May:
- Coverage report for all developed cases in CTG/ISAC has been generated and it is reported as 100%
- Currently real world test cases are being developed as per test plan and will be completed and send for review by beginning of next week
- Status from IIT Madras as on 05-May:
- Resolved issues in running the rv64ik toolchain after interacting with PLCT and compile the relevant tests generated from CTG and run them on spike
- Currently resolving issues in the running the rv64ibk toolchain. Once this is done, will generate the coverage report of the test cases built till now and share with team.
- Status from IIT Madras as on 26-Apr:
- Completed the coverage points specification for all 32-bit and 64-bit instructions
- Generated test cases from the coverage points
- Currently working on trying to install the scalar crypto enabled toolchain.
Compilers / Toolchains
Imperas maintain pre-built toolchains for various in-progress RISC-V extensions here. See the "rvk-*" branches for scalar crypto.
GCC and Binutils
- Experimental / development toolchain available in the riscv-crypto repository.
- This cannot be up-streamed, but can be used for development work for now.
- Intrinsics proposal from Markku
- PLCT lab have developed complete Binutils and GCC patches.
- The pull requests into the main RISC-V repos can be found here:
- Binutils pull request: https://github.com/riscv/riscv-binutils-gdb/pull/254
- GCC pull request: https://github.com/riscv/riscv-gcc/pull/250 (merged)
- The PLCT lab continuous integration server can be found here:
- https://ci.rvperf.org/view/Krypto-Scalar/
- This is a good place to start for re-producing the PLCT builds of GCC/Binutils
- Some small changes will be needed as we move to v1.0 of scalar crypto around encodings.
- The pull requests into the main RISC-V repos can be found here:
LLVM
- Work will be done by PLTC lab under the group contributor model.
- Slides from PLCT Update Weds 10'th Feb
- As of 21'st April '21, LLVM work is mostly complete, waiting on PLCT lab for an update about merging things upstream.
- Some small changes will be needed as we move to v1.0 of scalar crypto around encodings.
Simulators
Though all listed under "simulators", these are actually a collection of formal model / virtual machine / architectural simulators / DV simulators etc.
SAIL
- Currently working on getting support merged in upstream in PR#99
- Support for all scalar-crypto dedicated instructions and the entropy source is present.
- No support for Bitmanip. The Bitmanip TG is waiting until after the opcode and consistency review to start writing SAIL code.
Spike
- Upstream support has been merged in.
- Instructions are up to date with v0.9.4.
- Entropy source PR for v0.9.4 is here.
riscvOVPSimPlus
- Imperas Commercial Simulator
- Freeware version
- Support for:
- Crypto-scalar v0.7.2, v0.81 + Bitmanip subsets
- Bitmanip 0.92, 0.93
- Functional coverage collection.
QEMU
- Work will be done by PLTC lab under the group contributor model.
- Github repository
- Continuous integration status
- Waiting to hear back from PLCT on status.
Proof-of-Concept implementations
Hardware
| Project Name | Base Architecture | Level of implementation | Notes |
|---|---|---|---|
| Stand-alone functional units | RV32/64 | Yosys Synthesis | Stand-alone functional-unit style implementations of the dedicated scalar crypto instructions. Free to use as "drop-ins" for prototyping. |
| scarv-cpu | RV32 | Behavioural RTL simulation / Yosys Synthesis / FPGA | Completely Public/Open Source. Useful as a public baseline. Commercial implementations should aim to be better than this! |
| PQShield security core | RV32 | (assumed) Behavioural RTL simulation. Running on FPGA. | Closed / commercial source - PQShield. |
| Minidice TRNG | N/A | FPGA Implementation | Closed / commercial source - PQShield. Complete implementation of the RISC-V entropy source. |
| Romain Dolbeau / VexRISC-V | RV32 | Running on FPGA. | Uses VexRiscv core as a base. Completely independent implementation from scratch, outside the Crypto TG. |
| IQonIC Works RV32IC_P5 | RV32 | In development | "implemented Zkn (...), along with selectable Zb* and Zkb. We also have an optional custom extension that does AES block encrypt/decrypt, and a bus-based AES/cipher-mode accelerator. Work in progress benchmarking them on FPGA to compare relative performance in accelerating crypto library functions." |
| croyde-riscv | RV64 | Behavioural RTL simulation / Yosys Synthesis / FPGA | 3-stage RV64 micro-controller. rv64imck. Free/Open source. Something commercial implementations should better. Implements everything except ZKR. |
We still need RV64 implementations. - Barry Spinney has offered to do advanced node synthesis runs for open source implementations.
- I (Ben) intend to take him up on this when I get time. No idea when that will be.
Software
| Project/Maintainer | Description |
|---|---|
| Romain Dolbeau | Independent implementations of various important ciphers + modes of operation. |
| rvkrypto-fips / Markku | "FIPS 140-3 and higher-level algorithm Tests for RISC-V Crypto Extension" |
| riscv-crypto benchmarks | Initial benchmarks used to develop the scalar crypto extension. |
ABI Extensions
- None required