Module ffi 

cfm_tc_* C ABI for the threshold-cryptography session interface.

These symbols are declared #[unsafe(no_mangle)] pub extern "C" and linked into whichever cdylib depends on confium-tc (today, confium-core’s libconfium cdylib, eventually a dedicated confium-ffi). The crate itself is an rlib, not a cdylib.

See TODO.roadmap/04-threshold-cryptography.md for the protocol rationale and crates/confium-core/src/ffi/rng.rs for the FFI pattern these entry points mirror.

Memory ownership

• CFMTcMessage **outgoing produced by cfm_tc_session_round is a heap array allocated by the framework; the caller frees it with cfm_tc_messages_destroy.
• CFMTcShare * produced by cfm_tc_dkg_output_share is a heap allocation; the caller frees it with cfm_tc_share_destroy.
• FFITcSession * is owned by the caller; destroy with cfm_tc_session_destroy.

Structs

CFMTcMessage

One inter-party message, C view. to_party_id == NULL means broadcast.

CFMTcMessageArray

Heap allocation returned by cfm_tc_session_round for the outgoing messages array. The framework owns the backing storage; the caller frees the whole bundle with cfm_tc_messages_destroy.

CFMTcPartyList

Roster of parties, C view.

CFMTcShare

A party’s share of a distributed secret, C view.

Enums

FFITcSession

Opaque session handle returned to C.

Functions

cfm_tc_dkg_output_share

For DKG sessions: extract the per-party share and the shared public key.

cfm_tc_messages_destroy

Free a CFMTcMessageArray returned by cfm_tc_session_round. Safe to call with NULL.

cfm_tc_session_create

Create a new threshold session.

cfm_tc_session_destroy

Destroy a session. Safe to call with NULL.

cfm_tc_session_result

Read the final session artifact into out.

cfm_tc_session_round

Step the session forward one round.

cfm_tc_share_destroy

Free a CFMTcShare returned by cfm_tc_dkg_output_share. Safe to call with NULL.