ouroboros/src/irmd/config.h.in, branch 0.24.0

build: Fix OpenSSL version check for PQC

2026-07-08T09:02:12+00:00

ML-KEM, ML-DSA and SLH-DSA all landed in OpenSSL 3.5.0, not 3.4.0. ML-KEM+ML-DSA and SLH-DSA can be disabled by DISABLE_ML / DISABLE_SLH. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

irmd: Deliver flow re-keying

2026-06-29T06:32:58+00:00

Re-key each encrypted flow's batch root periodically so a long-lived flow never exhausts or over-uses a single root. The IRMd re-runs the OAP exchange with the peer IRMd over the flow-update relay. The per-flow re-keying state is tracked in the registry (reg_flow). A re-key delivers one root seed from the OAP exchange. keyrot immediately HKDF-expands it into 128 node keys (KR_NODES_SZ = 128 × 32 B) and wipes the root. Then each of the 128 node keys is itself a root → HKDF-expanded into 64 (2^KEY_NODE_BITS) leaf keys, forked per direction; each leaf key is the actual AEAD key, good for 2^20 packets (the low counter bits are its nonce/seq). If the number of keys runs low, a re-key will be triggered (KEY_REKEY_WATERMARK). The rekey is signalled out of band to the application. The rbuff ACL is generalized into a flags word, so an RB_REKEY bit rides alongside the access RB_RD/RB_WR and FLOWDOWN/FLOWPEER bits. The RD and WR bits are revised ditching the fcntl historical weirdness. The seed is pulled via flow_read/flow_write, installed with crypt_rekey(). TX holds the old epoch until the peer is observed on the new one (or a grace deadline elapses), promoted from both the read and write paths so a recv-mostly flow still advances. Also fix the FLOW_ACCEPT and FLOW_ALLOC handlers, which on a key-buffer allocation failure returned from inside the cleanup-push region: that leaked the reply message and skipped both the stack-key scrub and the cleanup pop. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

irmd: Bound the OAP replay cache

2026-06-29T06:32:58+00:00

Replace the linked-list cache with three timestamp-generation hash buckets, each capped at OAP_REPLAY_MAX entries. A bucket is an open-addressed hash set whose slots count as live only while slot.gen equals the bucket generation, so a stale bucket clears in O(1) by bumping its generation instead of being scanned and pruned. On overflow the cache fails closed - it rejects the header rather than evicting the oldest entry. Under flood, dropping a genuine entry would let that header be replayed, so refusing new entries is the safer degradation than evict-oldest (fail-open) behaviour. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

irmd: Specify peer authentication contract

2026-06-29T06:32:58+00:00

OAP accepted requests and responses without a certificate even when the peer was expected to authenticate. An on-path attacker could strip the certificate and signature from a flow allocation response and substitute its own key exchange, silently downgrading the handshake to unauthenticated. Add an auth=required|optional policy to enc.conf, enforced per role: a client config requires the server to present a valid certificate, a server config requires the same from the client. Default is required for client side (https), optional server side. The client side default can be changed via OAP_CLIENT_AUTH_DEFAULT for testing. Replace the bare 'none' keyword with encryption=none, which disables encryption only: the digest and the authentication policy are kept, so authenticated but unencrypted flows can be configured. Configs using bare 'none' are now rejected. 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 SLH-DSA tests and per-algorithm PQC gating

2026-02-18T06:53:35+00:00

This replaces the single HAVE_OPENSSL_PQC/DISABLE_PQC with per-algorithm CMake variables (ML-KEM, ML-DSA, SLH-DSA), gated by the OpenSSL versions: ML-KEM and ML-DSA require >= 3.4, SLH-DSA >= 3.5. SLH-DSA was already working, but now added explicit authentication tests for it with a full certificate chain (root CA, intermediate CA, server) to show full support. Rename PQC test files and cert headers to use algorithm-specific names (ml_kem, ml_dsa, slh_dsa) and move cert headers to include/test/certs/. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Add per-user packet pools

2026-02-13T08:22:28+00:00

The IRMd will now check the user UID and GID for privileged access, avoiding unprivileged users being able to disrupt all IPC (e.g. by shm_open the single pool and corrupting its metadata). Non-privileged users are now limited to a PUP (per-user pool) for sending/receiving packets. It is still created by the IRMd, but owned by the user (uid) with 600 permissions. It does not add additional copies for local IPC between their own processes (i.e. over the local IPCP), but packets between processes owned by a different user or destined over the network (other IPCPs) will incur a copy when crossing the PUP / PUP or the PUP / GSPP boundary. Privileged users and users in the ouroboros group still have direct access to the GSPP (globally shared private pool) for packet transfer that will avoid additional copies when processing packets between processes owned by different users and to the network. This aligns the security model with UNIX trust domains defined by UID and GID by leveraging file permission on the pools in shared memory. ┌─────────────────────────────────────────────────────────────┐ │ Source Pool │ Dest Pool │ Operation │ Copies │ ├─────────────────────────────────────────────────────────────┤ │ GSPP │ GSPP │ Zero-copy │ 0 │ │ PUP.uid │ PUP.uid │ Zero-copy │ 0 │ │ PUP.uid1 │ PUP.uid2 │ memcpy() │ 1 │ │ PUP.uid │ GSPP │ memcpy() │ 1 │ │ GSPP │ PUP.uid │ memcpy() │ 1 │ └─────────────────────────────────────────────────────────────┘ This also renames the struct ai ("application instance") in dev.c to struct proc (process). Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Replace rdrbuff with a proper slab allocator

2026-01-26T06:50:33+00:00

This is a first step towards the Secure Shared Memory (SSM) infrastructure for Ouroboros, which will allow proper resource separation for non-privileged processes. This replaces the rdrbuff (random-deletion ring buffer) PoC allocator with a sharded slab allocator for the packet buffer pool to avoid the head-of-line blocking behaviour of the rdrb and reduce lock contention in multi-process scenarios. Each size class contains multiple independent shards, allowing parallel allocations without blocking. - Configurable shard count per size class (default: 4, set via SSM_POOL_SHARDS in CMake). The configured number of blocks are spread over the number of shards. As an example: SSM_POOL_512_BLOCKS = 768 blocks total These 768 blocks are shared among 4 shards (not 768 × 4 = 3072 blocks) - Lazy block distribution: all blocks initially reside in shard 0 and naturally migrate to process-local shards upon first allocation and subsequent free operations - Fallback with work stealing: processes attempt allocation from their local shard (pid % SSM_POOL_SHARDS) first, then steal from other shards if local is exhausted, eliminating fragmentation while maintaining low contention - Round-robin condvar signaling: blocking allocations cycle through all shard condition variables to ensure fairness - Blocks freed to allocator's shard: uses allocator_pid to determine target shard, enabling natural load balancing as process allocation patterns stabilize over time Maintains existing robust mutex semantics including EOWNERDEAD handling for dead process recovery. Internal structures exposed in ssm.h for testing purposes. Adds some tests (pool_test, pool_sharding_test.c. etc) verifying lazy distribution, migration, fallback stealing, and multiprocess behavior. Updates the ring buffer (rbuff) to use relaxed/acquire/release ordering on atomic indices. The ring buffer requires the (robust) mutex to ensure cross-structure synchronization between pool buffer writes and ring buffer index publication. 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