Root cause: db_handle_init_resp marked sync_state=2 when my_dh==peer_dh
without checking that all my records fit in the confirmed prefix.
If mc > tp+1 (I have records beyond the common prefix), the tail was
never sent — lost records.
Fix:
- Remove special-case 'sc==0 && my_dh==peer_dh' (redundant, same bug)
- In general dh_match: if mc > tp+1, send remaining records [tp+1,mc-1]
using the same inline loop pattern as 'peer empty' branch
Test: 3 phases covering all dh_match paths:
- Phase 1: B empty+late instance → dh_match at tp=0 (sc=0) → tail-send 49
- Phase 2: A=80 B=50 → dh_match at tp=49 (sc>0, sparse) → tail-send 30
- Phase 3: fresh instances → peer empty → send all 30
- db_sync_on_conn_up: per-instance synced/skipped counters
- db_sync_peer_check_cb: summary INFO of check results
- db_sync_instance_add: peers_found + peers_synced counts
- db_handle_init_sync/initiate_sync: enhanced with tbl name
- db_handle_init_resp: tp + my_mc in sync complete/dh match
- db_handle_send_data: range + SYNC_DONE details; stop reason when mc>pk
- db_handle_sync_done: both counts + datahashes in mismatch; dh in confirm
- db_sync_recv_cb: INFO when instance NOT FOUND (timing race)
- cs_handle_channel_info_resp: sync readiness after channel ready
- cs_handle_welcome: note about db_sync peer_check timer
- on_db_sync_insert: counter (#1-3 then every 10) with ch/n/ts/dh/ct
etcp_conn_set_peer_node_id at state=0 updates conn->peer_node_id but
does not reindex the queue entry (key stays 0). Check the queue entry
directly to detect unindexed outbound connections.
- chat_core.c: CREATE TABLE IF NOT EXISTS peers_* in ensure_channel_ready
- utun_node.cpp: GUI_ERROR redirected to debug log file via guiDebugFile()
- etcp_connections.c: reuse unindexed outbound conn (peer_node_id==0)
on cross-connect INIT to avoid 'Can not insert link to socket'
Router deliver now visible without trace — shows svc_id, len, remote_node_id, conn ptr, callback ptr
This will confirm whether CHANNEL_INFO_REQ reaches chat_sync on the server side
- cs_find_conn_for_node: show queue state, entry found/missing, conn flags
- cs_on_conn_up: log when skipping due to !initialized
- etcp_conn_queue_set_ready: log reindex details (old/new entry, count)
- etcp_conn_set_peer_node_id: show state+reindexed flag
- utun_instance.h: add chat_connections queue (indexed by node_id, 8 bytes)
- chat_sync.c: queue_new in init, queue_free in destroy, queue_find_data_by_index in cs_find_conn_for_node
- chat_sync.c: remove from queue in cs_on_conn_down
- chat_core.c: add to queue in connect_from_invite and connect_auto
- chat_core.c: remove from queue in cc_parallel_cleanup and ca_cleanup
- db_sync.c: replace linear conn search with queue_find_data_by_index (db_sync_send_hash)
- etcp_connections: keepalive SEND/RECV/DECRYPT_OK: DEBUG→TRACE; DECRYPT_FAIL: WARN→DEBUG
- db_sync_on_conn_up: skip sync if !conn->initialized, wait for next UP event
- db_sync peer_check_timer+instance_add: also check conn->initialized
- chat_sync cs_on_conn_up: ignore conn_up before initialized (cs_send fails otherwise)
- db_sync_on_conn_up log now includes init= and links=
- Replace db_sync_stub.c with real src/db_sync.c in libutun
- Remove message sync protocol from chat_sync (INIT_SYNC/INIT_RESP/SEND_DATA/PUSH/ACK_PUSH/SYNC_DONE)
- Keep chat_sync auxiliary: join protocol, peer management, auto-connect
- Remove chat_core_insert_record, cursor_*, mark_sent/ttl_delete stubs
- chat_core on_db_sync_insert now only does SQLite INSERT + GUI notify
- Move db_sync_init() from instance_init_common to utun_instance_init for config override timing
- Force db_sync_enabled=1 in utun_node.cpp
- db_sync handles all P2P message sync via service 0x20
When etcp_conn_reinit is called, it clears ETCP queues (input_wait_ack
etc.) which frees dgram objects to data_pool. If a router retransmit
timer fires concurrently, it sends through the same conn → normalizer
allocates from corrupted data_pool → SIGSEGV.
Fix: call etcp_router_pause_retrans_for_node() BEFORE etcp_conn_reset()
to cancel retrans timers and free inflight_q entries for all router
connections to the peer. No callbacks, no close notifications —
lightweight pause, router connections stay alive and resume when
ETCP connection comes back up.
Added callbacks_running flag to ETCP_CONN:
- set to 1 before up_cbks / down_cbks / ready_cbks iteration
- reset to 0 after iteration completes
- etcp_connection_close checks flag and does intentional SIGSEGV
with FATAL log message if called during callback chain
This catches illegal synchronous close from within callbacks
instead of producing cryptic UAF segfaults later.
Protocol: added collision field to INIT_REQUEST_PKT (1 byte before ed25519_pubkey).
When two peers connect simultaneously, the one with is_server=0 (API-created
outbound link) is the master. Resolution by smaller node_id:
- We have master link + smaller node_id → send our INIT with collision=1
- We have master link + larger node_id → yield, process as slave
- Remote sends collision=1 → become slave unconditionally
- session_id change always forces reinit (genuine restart)
Removed unconditional etcp_conn_reinit on INIT_RESPONSE(0x03) — guarded by
reset_done flag. Server-side reinit now has collision check BEFORE reset_done
guard; session_id change penetrates reset_done protection.
Closes cross-connect reinit loop causing endless UP/DOWN flapping.
In etcp_conn_ready / etcp_on_up / etcp_on_down / etcp_connection_create /
tcp_server_on_link, callback chains were iterated with:
while (cbe) { cbe->fn(...); cbe = cbe->next; }
If the callback removes itself from the chain (e.g. ca_ready_cb calls
etcp_conn_remove_ready_cbk which u_free's the entry), cbe->next reads
freed memory → SIGSEGV.
Fixed by saving next pointer before invoking the callback:
while (cbe) { n = cbe->next; cbe->fn(...); cbe = n; }
Problem: when two peers connect simultaneously, each incoming
INIT_REQUEST(0x02) or INIT_RESPONSE(0x03) triggers etcp_conn_reinit
unconditionally, causing endless UP/DOWN flapping loop.
Fix: add reset_done flag to ETCP_CONN:
- 0 at creation and after explicit reinit (reinit allowed)
- set to 1 in etcp_conn_ready (connection stable, block reinit)
Three call sites guarded with !conn->reset_done:
- client: handle_init_response_client (INIT_RESPONSE 0x03)
- server: existing link INIT_REQUEST processing
- server: new link INIT_REQUEST processing
send_reset logic preserved unconditionally — only etcp_conn_reinit
itself is blocked when already stable.
- RECV: log every packet (src addr, link found, session_ready, decrypt result)
- RECV: log init decrypt rejection with packet code (catches 0x03 INIT_RESPONSE
silently dropped by init path)
- SEND: log destination addr+fd in send_init_response and etcp_encrypt_send
- REINIT: log full reason in server and client paths (code, session, got_init,
initialized, links_up state before reinit)
When two peers send INIT simultaneously, the first link occupies the socket.
Incoming INIT arriving after finds the existing outbound link by (ip,port)
instead of failing with 'Can not insert link to socket'.
- chat_core_connect_auto: direct ETCP connect from SQLite (no BGP)
- auto_connect: parallel connect to peers with 3s timeout, retry 10s
- RTT saved to node_addresses on disconnect
- vertical status bar + circle badge with online count per channel
- ChannelListView prevents deselection
- Replace get_time_us() with utun_gettimeofday() for PUSH message timestamps
(db_sync.c, chat_core.c) — monotonic clocks differ across Linux/Windows
- Fix merkle_sync: restart session timer in _handle_request to prevent
double-sided timeout when both nodes start member_sync simultaneously
- Fix INIT_RESP short-format: don't mark synced when my_count > peer_count
- Add db_sync_get_last_timestamp() to avoid duplicate timestamp generation
between db_sync and chat_core on_db_sync_insert
- Fix db_sync_stub to generate timestamps consistently
- build.sh: auto-rebuild chatgui via CMake after utun build
new_conn is only true for the first INIT after server restart.
Subsequent INITs from same peer (recovery loop) see new_conn=0
and revert to old logic, sending 0x05 (no reset) and overwriting
the first 0x03 response.
got_initial_pkt stays 0 until client actually sends seq=1, so
server keeps sending 0x03 across all INIT retries until client
resets and starts from seq=1.
When server restarts, new ETCP_CONN has session_id=0 (calloc).
If client sends INIT_REQUEST_NOINIT (0x04) with session_id=0,
the condition conn->session_id != session_id is false (both 0),
so no reset was sent. Client kept old seq numbers while server
expected seq=1, causing 'Waiting for initial packet' deadlock.
Fix: add || new_conn to the condition — when server created a
fresh connection (was restarted), always send reset to client.
Server now checks both code==ETCP_INIT_REQUEST and session_id mismatch
to decide send_reset. Previously only session_id was checked, so if
session matched (both sides had 00000000), reinit was skipped even
when client explicitly requested reset (code 0x02).
Client side already correct: handle_init_response_client:1473 calls
etcp_conn_reinit if pkt_code==ETCP_INIT_RESPONSE (0x03).
- 1133: DEBUG_DEBUG -> DEBUG_INFO for TX DATA (seq, len, retry, queue lengths)
- 1437: add DEBUG_INFO when initial packet seq=1 accepted
These two INFO lines show the exact order of first sends and receives
to diagnose INIT sequencer sync without guessing.
- 1556: Normal decryption failed -> DEBUG_DEBUG (expected for INIT, no more spam)
- 1581: added 'INIT X25519 OK from %s' with source address
- 1604-1617: INFO log for decrypted packet type (PING/PONG/INIT) with peer_id+src
- 1662-1668: expanded INIT accepted log with all fields:
peer_id, mtu, link_id, socket_id, type, only_local, src_ip:src_port,
session_id, actual src (UDP) — shows NAT mismatch
Without sc_init_ctx, crypto_ctx.initialized==0, sc_set_peer_public_key returns
SC_ERR_NOT_INITIALIZED, and all subsequent sc_encrypt (INIT, etc) fail with
'encryption failed' error 2. Fixed in cm_start_phase_direct and
reverse-connect path (both places that create ETCP_CONN for conn_mgr).
Evgeny