Extends the previously verify-only ed25519.c with ed25519_keygen() and ed25519_sign() per RFC 8032 5.1.5/5.1.6, reusing every point-arithmetic primitive verify already had -- only seed expansion/clamping and per-message nonce derivation are new. Signing is deterministic; only keygen ever touches entropy, via a caller-supplied seed (virtio_rng, Phase A) -- keygen still generates nothing itself. New scalar_muladd() (scalar25519.c) for signing's S = (k*a + r) mod L, the one scalar op verify never needed. Schoolbook multiply into a u128 wide accumulator with one final carry pass -- deliberately the same shape as fe25519.c's existing multiply, which has a documented history of a real bug from carrying mid-accumulation instead of in one pass. Verified against an independent implementation, not self-consistency: a throwaway host harness against Python's cryptography library (OpenSSL- backed) across 6 trials (5 random seed/message pairs + the empty-message case) produced byte-for-byte identical pubkeys and signatures every time. Clean compile on all three architectures and a full 3-arch QEMU acceptance boot, conservation intact, no panics or guest errors. Nothing calls the new functions from the live kernel path yet -- that's Phase C (the MINT word itself), still open, documented in FABRIC-3.md. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01U14ET9CWAtbQMbYqomKgXd
src/starkernel/
LithosAnanke — the bare-metal UEFI kernel that boots StarForth directly on
hardware (amd64/aarch64/riscv64). Built only via Makefile.starkernel; the
only valid acceptance test is the three-arch QEMU boot (see
.claude/CLAUDE.md), never make test.
kernel_main.c— kernel entry point, driving the boot milestones (console init, PMM, VMM, interrupts, timers, kmalloc heap, VM bootstrap).repl.c— kernel REPL.doe_log.c— kernel-side DoE (Design of Experiments) metrics logging.
Subdirectories:
arch/{amd64,aarch64,riscv64}/— per-architecture support (APIC/GIC/ PLIC interrupt controller, timers, boot/ISR assembly).boot/— UEFI loader, ELF loading, kernel command-line parsing.capsule/— capsule birth/run/load/validate pipeline.hal/— hardware-abstraction-layer implementation (console, framebuffer, VT100, memory, host services).hash/— XXHash64 content-addressing implementation.math/— kernel-build Q48.16 fixed-point arithmetic.memory/— physical/virtual memory managers and the kernel heap.pci/— PCI bus enumeration.virtio/— VirtIO block device driver.vm/— kernel VM subsystem (bootstrap, core interpreter, parity logging, capsule arena).
See include/starkernel/README.md for the corresponding headers.