ouroboros/src/ipcpd/local/main.c, branch master

build: Update copyright to 2026

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

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

ipcpd: Update DHT for unicast layer

2025-08-06T10:34:15+00:00

This is a rewrite of the DHT for name-to-address resolution in the unicast layer. It is now integrated as a proper directory policy. The dir_wait_running function is removed, instead the a DHT peer is passed on during IPCP enrolment. Each DHT request/response gets a random 64-bit ID ('cookie'). DHT messages to the same peer are deduped, except in the case when the DHT is low on contacts. In that case, it will contact the per it received at enrolment for more contacts. To combat packet loss, these messages are not deduped by means of a 'magic cookie', chosen at random when the DHT starts. The DHT parameters (Kademlia) can be set using the configfile or the IRM command line tools: if DIRECTORY_POLICY == DHT [dht_alpha (default: 3)] [dht_k (default: 8)] [dht_t_expire (default: 86400)] [dht_t_refresh (default: 900)] [dht_t_replicate (default: 900)] This commit also adds support for a protocol debug level (PP). Protocol debugging for the DHT can be enabled using the DEBUG_PROTO_DHT build flag. The DHT has the following message types: DHT_STORE, sent to k peers. Not acknowledged. DHT_STORE --> [2861814146dbf9b5|ed:d9:e2:c4]. key: bcc236ab6ec69e65 [32 bytes] val: 00000000c4e2d9ed [8 bytes] exp: 2025-08-03 17:29:44 (UTC). DHT_FIND_NODE_REQ, sent to 'alpha' peers, with a corresponding response. This is used to update the peer routing table to iteratively look for the nodes with IDs closest to the requested key. DHT_FIND_NODE_REQ --> [a62f92abffb451c4|ed:d9:e2:c4]. cookie: 2d4b7acef8308210 key: a62f92abffb451c4 [32 bytes] DHT_FIND_NODE_RSP <-- [2861814146dbf9b5|ed:d9:e2:c4]. cookie: 2d4b7acef8308210 key: a62f92abffb451c4 [32 bytes] contacts: [1] [a62f92abffb451c4|9f:0d:c1:fb] DHT_FIND_VALUE_REQ, sent to 'k' peers, with a corresponding response. Used to find a value for a key. Will also send its closest known peers in the response. DHT_FIND_VALUE_REQ --> [2861814146dbf9b5|ed:d9:e2:c4]. cookie: 80a1adcb09a2ff0a key: 42dee3b0415b4f69 [32 bytes] DHT_FIND_VALUE_RSP <-- [2861814146dbf9b5|ed:d9:e2:c4]. cookie: 80a1adcb09a2ff0a key: 42dee3b0415b4f69 [32 bytes] values: [1] 00000000c4e2d9ed [8 bytes] contacts: [1] [a62f92abffb451c4|9f:0d:c1:fb] Also removes ubuntu 20 from appveyor config as it is not supported anymore. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

ipcpd: Refactor ipcp main struct

2025-07-23T13:07:59+00:00

The ipcpi (IPCP instance) is now cleanly tucked away within its source file instead of exposed all over the place. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

ipcpd: Mitigate race in wait_req_arr and wait_resp

2024-02-26T07:59:15+00:00

The wait_flow_req_arr and wait_flow_resp functions are there to ensure the responses of the IRMd to flow allocation requests arrive in the correct order. These functions use a mutex: alloc_lock. After these functions return, the IPCP will switch to it's own (usually read-write) lock. In the local IPCP, this leaves room for a race where the state of the flow is accessed in alloc_resp before it is updated in wait_flow_req_arr. This race is only visible in the local IPCP, as the other IPCP have to send information between these calls, but it is theoretically possible when using any IPCP for local IPC. In the ipcpd-local, it happens ~0.01% to ~0.03% of flow allocations. This mitigates the problem in the ipcpd-local by adding a 1ms wait to the flow allocation if this race is detected. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

irmd: Fix flow deallocation timeout

2024-02-26T07:59:15+00:00

The timeout was set to a value calculated as abstime for a cond_wait instead of a timeout, causing flows to linger in the IPCP. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Revise app flow allocation

2024-02-23T15:41:37+00:00

This revises the application flow allocator to use the flow_info struct/message between the components. Revises the messaging to move the use protocol buffers to its own source (serdes-irm). Adds a timeout to the IRMd flow allocator to make sure flow allocations don't hang forever (this was previously taken care of by the sanitize thread). 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

include: Use common definition between lib and IRMd

2024-01-31T09:27:56+00:00

Some definitions/enums were different between the library and IRMd (flow_state, ipcp_state). This moves them to common ground. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders