OQ-59 resolved to Option A: fingerprint.rs stays in alknet-core. The
client-side FingerprintPinVerifier in alknet-call uses fingerprint
functions and must not depend on alknet-tls (which would pull TLS setup
infra into client-only deployments). The rustls dep in core is narrow —
production fingerprint code uses only sha2 + manual DER parsing; the
rustls::sign usage is a test helper only. alknet-tls re-exports the
fingerprint functions for convenience.
ADR-084: aws-lc-rs as the TLS crypto provider on all server + client
config paths. Records the decision that was already in the code (to
match iroh's tls-aws-lc-rs feature) but had no ADR. FIPS-capable, broad
platform support, consistent across quinn/iroh/TCP+TLS/client. Switching
to ring or process-default requires a new ADR. ADR-082's
behavior-preservation invariant now references ADR-084 for the decision
record.
The TLS setup in alknet-core is welded to quinn: build_rustls_server_config
produces a rustls::ServerConfig, then build_quinn_server_config_from_rustls
consumes it into quinn::ServerConfig — the rustls config is moved, not
shareable. ACME is worse: the AcmeState task is spawned inside the quinn
endpoint, so a TCP+TLS listener would need a second ACME state machine
(two orders for the same domain, two cert caches, Let's Encrypt
rate-limit risk).
alknet-tls extracts the TLS setup into a shareable TlsServerConfig:
- TlsServerConfig::new(identity, alpns) builds the rustls::ServerConfig
once (including the ACME state machine if ACME)
- for_quinn() clones it for quinn (QuicServerConfig::try_from)
- for_tcp_tls() clones it for tokio-rustls (TlsAcceptor::from)
- rustls_config() borrows it for any other consumer
- One cert, one ACME state machine, N transports
TlsIdentity and Ed25519SecretKey stay in core (config types).
fingerprint.rs stays in core (shared by server endpoint + client
FingerprintPinVerifier in alknet-call — OQ-59 tracks whether it should
move; likely stays because moving would force alknet-call to depend on
alknet-tls, pulling TLS infra into client-only deployments).
iroh shares the key, not the rustls config — iroh has its own TLS built
into the Endpoint (takes iroh::SecretKey, not rustls::ServerConfig).
alknet-tls has no for_iroh() method; the assembly layer passes
Ed25519SecretKey to iroh directly.
Feature gates: quinn / tcp / acme as independent opt-ins. rustls always
present. tokio-rustls only when tcp. quinn only when quinn. rustls-acme
only when acme.
Files:
- crates/tls/README.md: crate spec (TlsServerConfig API, what moves/
stays, feature gates, deps, behavior-preservation invariants)
- decisions/082-alknet-tls-extraction.md: the ADR (Proposed)
- questions/059-fingerprint-module-location.md: OQ-59 (should
fingerprint.rs stay in core or move to alknet-tls? open, two-way,
likely stays)
- open-questions.md: OQ-59 added to alknet-core table
- README.md: tls doc table row + ADR-082 row added
Review (architecture-reviewer): 3 critical (missing
build_quinn_server_config_from_rustls in README table, missing futures
dep, two TlsServerConfig code blocks disagreed on feature gates), 7
warnings (behavior-preservation invariants: max_early_data_size,
aws_lc_rs provider, verifier scheme list, acme-tls/1 ALPN;
rustls-pki-types dep; fingerprint.rs rustls-usage imprecision; ADR
missing acme-tls/1), 4 suggestions. All criticals and warnings addressed.
glm-5.2