Module inprocess 

In-process synchronous driver for CMP20 DKG and signing.

Thin wrapper over confium_tc::inprocess that names the CMP20 schemes and pulls the joint public key out of the first share. All multi-round routing logic lives in the framework driver; this module is intentionally short.

Output wire format

keygen returns (shares, public_key) where:

• shares[i] is the opaque Cmp20Share::to_bytes() encoding for party i (71 bytes: magic[4] | version[1] | x_i[32] | X[33] | idx[1]).
• public_key is the 33-byte SEC1 compressed encoding of the joint P-256 point.

sign returns a 64-byte r || s ECDSA signature. Verify it with the [p256::ecdsa] crate’s VerifyingKey::verify.

Security note

The underlying CMP20 crate’s MtA sub-round is a simplified in-clear stub. This driver inherits that property. See crate::mta for the gap.

Structs

KeygenOutput

Outcome of a single CMP20 DKG run: N share blobs plus the joint public key.

Functions

decode_public_key

Decode a 33-byte SEC1 compressed P-256 point. Public so bindings can verify the DKG-produced joint public key out-of-band.

keygen

Drive the CMP20 non-interactive DKG in-process for party_count parties at threshold threshold.

sign

Drive a CMP20 signing session in-process using share_blobs (each a Cmp20Share::to_bytes() blob from a previous keygen) at threshold threshold. Returns the 64-byte (r, s) ECDSA signature.

sign_batch

Sign messages.len() messages against the same joint key without re-running DKG. Reuses the same share_blobs for every message.