ouroboros/src/irmd/reg/tests/flow_test.c, branch 0.24.0

lib: Update FRCP implementation

2026-05-20T06:17:07+00:00

The Flow and Retransmission Control Protocol (FRCP) runs end-to-end between two peers over a flow. It provides reliability, in-order delivery, flow control, and liveness. Note that congestion avoidance is orthogonal to FRCP and handled in the IPCP. A fixed 16-octet header, network byte order, is prefixed to every FRCP packet: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | flags | hcs | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | window | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | seqno | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ackno | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | payload (variable) ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ hcs is a CRC-16-CCITT-FALSE checksum over the PCI (and the stream extension when present), verified before any flag-driven dispatch. A single packet can simultaneously carry DATA + ACK + FC + RXM by OR-ing flag bits. An optional CRC trailer covers the body on DATA when qs.ber == 0, and on every SACK packet; an optional AEAD wrap (per-flow keys) sits outermost. Flag bits (MSB-first; bits 13..15 reserved, MUST be zero): +------+--------+--------+----------------------------------------+ | Bit | Mask | Name | Meaning | +------+--------+--------+----------------------------------------+ | 0 | 0x8000 | DATA | Carries caller payload | | 1 | 0x4000 | DRF | Start of a fresh data run | | 2 | 0x2000 | ACK | ackno field valid | | 3 | 0x1000 | NACK | Pre-DRF nudge (seqno informational) | | 4 | 0x0800 | FC | window field valid (rwe advertisement) | | 5 | 0x0400 | RDVS | Rendezvous probe (window-closed) | | 6 | 0x0200 | FFGM | First Fragment of a multi-fragment SDU | | 7 | 0x0100 | LFGM | Last Fragment of a multi-fragment SDU | | 8 | 0x0080 | RXM | Retransmission | | 9 | 0x0040 | SACK | Block list follows in payload | | 10 | 0x0020 | RTTP | RTT probe / echo (payload follows) | | 11 | 0x0010 | KA | Keepalive | | 12 | 0x0008 | FIN | End of stream marker | | 13-15| -- | -- | Reserved (MUST be zero) | +------+--------+--------+----------------------------------------+ (FFGM, LFGM) encodes the fragment role of a DATA packet (SCTP-style B/E): 11=SOLE, 10=FIRST, 00=MID, 01=LAST. Each fragment carries its own seqno; Retransmission recovers fragments individually, reassembly runs at consume time. In stream mode FFGM/LFGM are unused; per-byte position is carried by the stream extension below and end-of-stream is signalled by FIN on a 0-byte DATA packet. SACK payload (FRCT_ACK | FRCT_FC | FRCT_SACK): 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | n_blocks | padding (2 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | start[0] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | end[0] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... n_blocks pairs total ... Each block describes a *present* (received) range strictly above the cumulative ACK in the PCI ackno. D-SACK (RFC 2883) is signalled in-band as block[0] - no flag bit, no extra framing - and consumed by the RACK reo_wnd_mult scaler (RFC 8985 sec. 7.2). RTTP payload (FRCT_RTTP only; 24 octets): 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | probe_id | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | echo_id | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + nonce (16 octets, echoed verbatim) + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Stream PCI extension (in_order == STREAM only; 8 octets after the base PCI on every DATA packet): 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | start | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | end | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ start, end are monotonic 32-bit byte offsets; end - start equals the on-wire payload length. Stream mode is negotiated at flow allocation; the extension is present iff stream mode is in use, never on a per-packet basis. Service modes are an orthogonal (in_order, loss, ber) vector selected at flow_alloc; the cubes above map to the axes: +----------------+---------+------+-----+-----------------------+ | Cube | in_order| loss | ber | Engaged | +----------------+---------+------+-----+-----------------------+ | qos_raw | 0 | 1 | 1 | Raw passthrough | | qos_raw_safe | 0 | 1 | 0 | Raw + CRC trailer | | qos_rt | 1 | 1 | 1 | FRCP, no FRTX, no CRC | | qos_rt_safe | 1 | 1 | 0 | FRCP, no FRTX, CRC | | qos_msg | 1 | 0 | 0 | FRCP + FRTX | | qos_stream | 2 | 0 | 0 | FRCP + FRTX, stream | +----------------+---------+------+-----+-----------------------+ in_order=0 sends raw datagrams with no PCI (UDP-equivalent); in_order=1 engages FRCP with SDU framing; in_order=2 (stream) requires loss=0 and is rejected otherwise. loss=0 engages the FRTX retransmit machinery. ber=0 appends the CRC-32 trailer; QOS_DISABLE_CRC at build time forces ber=1 for development. Encryption is a separate per-flow attribute layered as an AEAD wrap outside the FRCP packet. Heritage: delta-t (Watson 1981) supplies timer-based connection management - no SYN/FIN handshake, the DRF marker, the t_mpl / t_a / t_r timers. RINA (Day 2008) supplies the unified flow_alloc(name, qos, ...) primitive and the orthogonal QoS-cube axes. Loss detection follows TCP/QUIC practice (RFCs 2018, 2883, 6582, 6298, 8985); RTT probing is nonce-authenticated like QUIC PATH_CHALLENGE. Adds oftp, a minimal file-transfer tool over an FRCP stream flow. The client reads from stdin or --in FILE and writes through a flow_alloc(qos_stream); the server (--listen) calls flow_accept and writes to stdout or --out FILE. Both sides compute a CRC-64/NVMe over the bytes they handle and print the result. The server rejects flows whose negotiated qs.in_order != STREAM. Two FRCP knobs are exposed via env vars on either side: OFTP_FRCT_RTO_MIN fccntl FRCTSRTOMIN (ns) OFTP_FRCT_STREAM_RING_SZ fccntl FRCTSRRINGSZ (octets) The ocbr_client gains an OCBR_QOS env var to pick the cube the client uses for flow_alloc; recognised values are raw, safe, rt, rt_safe, msg, stream. Unknown values fall back to raw with a warning on stderr. Without the env set behaviour is unchanged. Removes the deprecated lib/timerwheel.c Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

irmd: Pass MTU from IPCP to process for FRCT

2026-05-20T06:17:06+00:00

FRCT needs to know the MTU for fragmentation. The MTU is now passed from the layer serving the flow to the process as part of flow allocation. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

irmd: Allow direct rbuff between local processes

2026-02-22T15:02:16+00:00

This allows bypassing the IPCP for local processes that share the same packet pool, lowering latency between processes to comparable levels as Unix sockets (RTT in the order of a microsecond). For local processes, no IPCPs are needed: $ irm b prog oping n oping $ oping -l Ouroboros ping server started. New flow 64. Received 64 bytes on fd 64. The direct IPC can be disabled with the DISABLE_DIRECT_IPC build flag. Note that this is needed for rumba 'local' experiments to emulate network topologies. Without this flag all processes will just communicate directly. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

build: Update copyright to 2026

2026-02-18T06:54:56+00:00

Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Add post-quantum cryptography support

2026-01-19T07:29:29+00:00

This adds initial support for runtime-configurable encryption and post-quantum Key Encapsulation Mechanisms (KEMs) and authentication (ML-DSA). Supported key exchange algorithms: ECDH: prime256v1, secp384r1, secp521r1, X25519, X448 Finite Field DH: ffdhe2048, ffdhe3072, ffdhe4096 ML-KEM (FIPS 203): ML-KEM-512, ML-KEM-768, ML-KEM-1024 Hybrid KEMs: X25519MLKEM768, X448MLKEM1024 Supported ciphers: AEAD: aes-128-gcm, aes-192-gcm, aes-256-gcm, chacha20-poly1305 CTR: aes-128-ctr, aes-192-ctr, aes-256-ctr Supported HKDFs: sha256, sha384, sha512, sha3-256, sha3-384, sha3-512, blake2b512, blake2s256 Supported Digests for DSA: sha256, sha384, sha512, sha3-256, sha3-384, sha3-512, blake2b512, blake2s256 PQC support requires OpenSSL 3.4.0+ and is detected automatically via CMake. A DISABLE_PQC option allows building without PQC even when available. KEMs differ from traditional DH in that they require asymmetric roles: one party encapsulates to the other's public key. This creates a coordination problem during simultaneous reconnection attempts. The kem_mode configuration parameter resolves this by pre-assigning roles: kem_mode=server # Server encapsulates (1-RTT, full forward secrecy) kem_mode=client # Client encapsulates (0-RTT, cached server key) The enc.conf file format supports: kex= # Key exchange algorithm cipher= # Symmetric cipher kdf= # Key derivation function digest= # Digest for DSA kem_mode= # Server (default) or client none # Disable encryption The OAP protocol is extended to negotiate algorithms and exchange KEX data. All KEX messages are signed using existing authentication infrastructure for integrity and replay protection. Tests are split into base and _pqc variants to handle conditional PQC compilation (kex_test.c/kex_test_pqc.c, oap_test.c/oap_test_pqc.c). Bumped minimum required OpenSSL version for encryption to 3.0 (required for HKDF API). 1.1.1 is long time EOL. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Swap len and data in the buffer_t

2025-07-25T14:24:46+00:00

This is how the ProtoBufCBinary data type is defined, so it will allow easier conversion until we get rid of it. But it makes sense, as the size_t will always be aligned. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Add authentication functions

2025-07-04T08:12:15+00:00

Adds functions needed for authentication using X509 certificates, implemented using OpenSSL. Refactors some library internals, and adds some unit tests for them. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

build: Fix missing newlines at end of file

2024-02-19T13:09:38+00:00

Some files had a newline at the end, others didn't. Now they all do. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

irmd: Revise IRMd internals

2024-02-19T10:49:07+00:00

This is a full revision of the IRMd internal implementation. The registry is now a proper subcomponent managing its own internal lock (a single mutex). Some tests are added for the registry and its data structures. Some macros for tests are added in . Flow allocation is now more symmetric between the client side (alloc) and server size (accept). Each will create a flow in pending state (ALLOC_PENDING/ACCEPT_PENDING) that is potentially fulfilled by an IPCP using respond_alloc and respond_accept primitives. Deallocation is split in flow_dealloc (application side) and ipcp_flow_dealloc (IPCP side) to get the flow in DEALLOC_PENDING and DEALLOCATED state. Cleanup of failed flow allocation is now properly handled instead of relying on the sanitizer thread. The new sanitizer only needs to monitor crashed processes. On shutdown, the IRMd will now detect hanging processes and SIGKILL them and clean up their fuse mountpoints if needed. A lot of other things have been cleaned up and shuffled around a bit. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders