- wo_tls_pem_to_ders: scan a PEM bundle for CERTIFICATE blocks, base64-decode
each into a caller arena, record DER spans as trust anchors for
wo_tls_verify_chain. Pure (caller reads the file + owns the arena) so it is
offline-testable; the file read + per-shard cache land with the builtin
- b64_decode helper (standard alphabet, skips whitespace/newlines)
- KAT: decode the real /etc/ssl/certs/ca-certificates.crt (>100 anchors,
each parses, first is a CA), garbage PEM -> 0 with no over-read,
skip-if-absent for CI. test_tls 107 pass, ASan/UBSan clean
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 6445d55aa83dbed831d84fd3cca3a74fe4609a00)
- crypto.c: x509_find_ext (generic extension walker) + wo_x509_basic_constraints
(cA / pathLenConstraint, absent => not a CA) + wo_x509_eku_serverauth_ok
(EKU absent, serverAuth, or anyEKU => usable; else not)
- wo_tls_verify_chain enforces decision 6: the leaf must be server-usable
(EKU), every server-sent issuer and the signing anchor must be a CA
(basicConstraints CA:TRUE) with a pathLenConstraint covering the
intermediates below it — stops a leaf masquerading as a CA
- gen_x509.py extended (folds in the wildcard leaf, adds EKU clientAuth-only,
EKU serverAuth, a non-CA intermediate + a leaf issued under it); vectors
regenerated
- KATs: extractors (test_crypto 104) + chain enforcement (test_tls 103) —
EKU serverAuth accepted, clientAuth-only rejected, leaf-under-non-CA
rejected though every signature verifies; existing chains still pass.
ASan/UBSan clean
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 3811418014c2c8d9bc3a9464256f52104261b1b9)
- wo_tls_verify_chain: leaf-first DER chain — each cert signed by the
next, the top trusted (equal to, or signed by, a trust anchor), the leaf
SAN matching host, every cert temporally valid. Any failure rejects;
no partial trust. Pure over the phase-D/E verifiers, so offline-testable
- KAT with the phase-E RSA + EC chains: leaf trusted via its issuing CA
anchor; wrong-anchor / wrong-host / expired / broken-link / no-anchor
all rejected; two-cert chain with a byte-equal root anchor; NULL host
skips the SAN check. test_tls 100 pass, ASan/UBSan clean
- remaining F3c-net (live-gated): CA-bundle PEM loader, random ephemeral,
the net.connect_tls builtin driving the sans-io driver over a real fd
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 9d40055108d301be32df0e1d4140c23446baa7c6)
- wo_x509_check_host: match a hostname against the cert subjectAltName
dNSNames (RFC 6125) — case-insensitive, single left-most wildcard that
covers exactly one label; no SAN => refused; no legacy CN fallback.
Completes the phase-E deferred hostname check (walks the [3] extensions)
- wo_tls_client_set_host + driver enforcement: with a host set, a leaf
whose SAN does not match is refused at the Certificate step (MITM
defense); unset skips the check (offline testing only, documented unsafe)
- KAT: exact/case-insensitive/mismatch, no-SAN refused, wildcard one-label
(not zero, not sub-label) via a wildcard-SAN cert; driver refuses the
RFC 8448 leaf (no SAN) once a host is set. test_crypto 95, test_tls 91,
ASan/UBSan clean
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 319ce8bfcf608030f958b36ab2c8f62fd76e1740)
- wo_tls_client: a pure state machine (no sockets). Caller frames
records; driver runs ClientHello->ServerHello->flight->Finished and
hands back bytes to send. Keeps all I/O out of the security-critical FSM
- start_with (inject CH + ephemeral priv), push_record, take_output,
encrypt/decrypt (application traffic keys). Handshake-message reassembly
across records; per-message transcript timing (CertVerify signs CH..Cert,
Finished MACs CH..CertVerify); constant-time Finished compare; every
failure lands in FAILED (no warn-and-continue)
- verifies server CertificateVerify (phase E+D) + server Finished, emits
the client Finished, switches to application keys
- KAT: whole handshake driven offline against the RFC 8448 record trace —
client Finished record byte-for-byte, first client app record
byte-for-byte, NewSessionTicket + server app data decrypt to plaintext,
tampered flight -> FAILED. test_tls 90 pass, ASan/UBSan clean
- SECURITY TODO before live use (documented in tls.h + story): chain walk
to a trust anchor + SAN/hostname match; random ephemeral for production
start; the net.connect_tls socket glue
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 74c332d7efdb8bbfdbe90bd2fcc3defa2fe8da00)
- wo_tls_verify_cert_verify: verifies a server CertificateVerify
(RFC 8446 §4.4.3) — builds the 64-space || context || 0x00 ||
transcript-hash content, parses the leaf SPKI (phase E) and dispatches
to phase-D RSA-PSS / RSA-PKCS1 / ECDSA-P256; the scheme must match the
leaf key type. ECDSA sig r/s pulled from its DER SEQ
- reuses wo_tls_finished_verify (phase F2) for server + client Finished
- KAT: the whole handshake crypto driven offline from the RFC 8448 §3
recorded messages — CertificateVerify (RSA-PSS) VALID, wrong-transcript
/ tampered-sig / mismatched-scheme rejected, server Finished byte-exact,
and the client Finished we would send byte-exact. test_tls 78 pass,
ASan/UBSan clean
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit afd9f23508c648322712df91329aa117c975ccab)
- new tls.c/tls.h on the crypto ladder: wo_tls_record_seal/open
(RFC 8446 §5.2) — TLSInnerPlaintext (content||type, no padding),
5-byte header as AEAD additional-data, per-record nonce = iv XOR
seq big-endian (§5.3)
- suite dispatch: TLS_AES_128_GCM_SHA256 (mandatory) +
TLS_CHACHA20_POLY1305_SHA256 (AES-NI-less fallback), over phase-A AEAD
- open() strips trailing zero padding to recover the inner content type;
rejects a length-field lie before the AEAD, and auth failure after
- KAT vs python AEAD oracle (test/gen_tls_record.py): sealed record
byte-for-byte both suites, open() recovers it, 5-seq round-trip,
tamper + wrong-seq + bad-suite rejected. test_tls 51 pass, ASan/UBSan
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 5021a99f8359f78a642bb0cc2b28ab66f6b624e2)
