Device libraries for the Tillitis TKey

C runtime: libcrt0.
Common C functions including protocol calls: libcommon.
Cryptographic functions: libmonocypher. Based on monocypher version 4.0.2 https://github.com/LoupVaillant/Monocypher

Relase notes in RELEASE.md.

Licenses and SPDX tags

Unless otherwise noted, the project sources are licensed under the terms and conditions of the "GNU General Public License v2.0 only":

Copyright Tillitis AB.

These programs are free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2 only.

These programs are distributed in the hope that they will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see:

https://www.gnu.org/licenses

See LICENSE for the full GPLv2-only license text.

External source code we have imported are isolated in their own directories. They may be released under other licenses. This is noted with a similar LICENSE file in every directory containing imported sources.

The project uses single-line references to Unique License Identifiers as defined by the Linux Foundation's SPDX project on its own source files, but not necessarily imported files. The line in each individual source file identifies the license applicable to that file.

The current set of valid, predefined SPDX identifiers can be found on the SPDX License List at:

https://spdx.org/licenses/

Building

In order to build, you must have the make, clang, llvm, and lld packages installed.

Version 15 or higher of LLVM/Clang is necessary for the RV32IC_Zmmul architecture we are using. For more detailed information on the supported build and development environment, please refer to the Developer Handbook.

Building using Podman

You can also build the libraries with our OCI image ghcr.io/tillitis/tkey-builder.

The easiest way to build this is if you have make installed:

make podman

You can also specify a different image by using IMAGE=localhost/tkey-builder-local.

Or use Podman directly:

podman run --rm --mount type=bind,source=.,target=/src -w /src -it ghcr.io/tillitis/tkey-builder:4 make -j

Minimal application build

You will typically need to link at least the libcrt0 C runtime otherwise your program won't even reach main().

We provide a linker script in apps.lds which shows the linker the memory layout.

Minimal compilation would look something like:

clang -target riscv32-unknown-none-elf -march=rv32iczmmul -mabi=ilp32 \
  -mcmodel=medany -static -std=gnu99 -O2 -ffast-math -fno-common \
  -fno-builtin-printf -fno-builtin-putchar -nostdlib -mno-relax -flto \
  -Wall -Werror=implicit-function-declaration \
  -I ../tkey-libs/include \
  -I ../tkey-libs -c -o foo.o foo.c

clang -target riscv32-unknown-none-elf -march=rv32iczmmul -mabi=ilp32 \
  -mcmodel=medany -static -ffast-math -fno-common -nostdlib \
  -T ../tkey-libs/app.lds \
  -L ../tkey-libs -lcrt0 \
  -I ../tkey-libs -o foo.elf foo.o

Makefile example

See example-app/Makefile for an example Makefile for a simple device application.

Debug output

If you're running the device app on our qemu emulator we have added a debug port on 0xfe00_1000 (TK1_MMIO_QEMU_DEBUG). Anything written there will be printed as a character by qemu on the console.

qemu_putchar(), qemu_puts(), qemu_putinthex(), qemu_hexdump() and friends (see include/tkey/qemu_debug.h for list of functions) use this debug port to print stuff.

If you want to use these, define QEMU_DEBUG when compiling your program, othwerwise all qemu_*() functions in your program are removed by the C pre-processor.

tkey-libs own use of qemu_*() is limited to output from assert(). This means that QEMU_DEBUG should be defined when compiling tkey-libs itself!

tillitis / tkey-libs

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