Phase B of the identity pipeline (FABRIC-3.md §F.7/§F.17):
- x509_ed25519.c/.h: two new DER walkers alongside the existing pubkey
extractor -- x509_verify_signature() (verifies a cert's outer Ed25519
signature over the raw, exactly-as-encoded tbsCertificate bytes, real
signature verification against issuer_pubkey, rejects non-Ed25519
signatureAlgorithm) and x509_extract_serial() (extracts the
serialNumber INTEGER, stripping a DER padding byte if present, for the
drive_uuid binding decided in §F.7).
- vm_identity.c: vm_identity_from_cert(), ties the three DER primitives
together into the actual CERTVERIFY check -- signature verifies against
issuer_pubkey, serialNumber matches this drive's own drive_uuid,
subject pubkey extracts cleanly -- and populates a VMIdentity on
success. acl_caps is caller-supplied, not read from the cert (nothing
in the decided cert fields encodes capabilities); deciding what a
verified identity is allowed to do is policy for the caller (WIREBIND,
not yet built), not this function's job.
Verified two ways: a standalone host-side test harness (not part of the
kernel build) links the real source files against a real openssl-
generated Ed25519 X.509 cert -- extracted pubkey, extracted serial, and
signature verification all match ground truth, plus two negative tests
(wrong issuer pubkey, corrupted signature) both correctly rejected. Then
the actual kernel build verified live on all three architectures: clean
compile, clean boot to ok>, Hermes/Artemis both live with no KILL. Same
pre-existing, unrelated Zuse fence-write anomaly observed on all three
(not caused by this change, not chased here).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019ZGkimpfyh63EZyRkNbkPD
Phase A of the identity pipeline (FABRIC-3.md §F.2/§F.16, §F.13):
- New include/starkernel/vm_identity.h: VMIdentity{owner_pubkey[32],
installed, acl_caps}, its own header per the project's "give real-shaped
data its own header" convention (VMUuid's own precedent), embedded by
value on struct VM. acl_caps is an independent capability bitmask, not
an ordered privilege tier (decided 2026-08-28) -- Zuse isn't a
structurally special VM, her identity just has every bit set
(VM_IDENTITY_CAP_ALL). No individual capability bits assigned yet,
deliberate slack matching blk_meta_t's own acl_reserved precedent --
real bits get names once the operation they gate (BINDSTEP, MINT, ...)
actually gets built.
- Applied the devblock-1 relocation decided in §F.13: new
HOMEBLOCKS_SIG_START_FBLOCK constant (homeblocks_sig.h), repl.c's
homeblocks_sig_check() call site updated from the literal 0. Also
applied the still-owed blockmap_offset/blockmap_devblocks ->
identity_src_offset/identity_src_devblocks rename decided in §F.6 (no
other code referenced the old names). Updated the header's own stale
GPT-relative doc comments to match -- GPT was dropped permanently, this
location is final, not an interim stand-in.
Verified live on all three architectures: clean compile, clean boot to
ok>, Hermes/Artemis both confirmed live with no KILL (no regression from
last session's session-less fix). One pre-existing, unrelated anomaly
observed consistently on all three arches, not caused by this change (no
code touched here intersects Zuse's own fence-write path): "Zuse: minted
but fence write FAILED (not persistent)" -- flagged for its own
investigation, not chased here.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019ZGkimpfyh63EZyRkNbkPD
