The Builder Vault TSM supports the following cryptographic signing operations:

Operation	Parameters
ECDSA	secp256k1
ECDSA	P-224
ECDSA	P-256
ECDSA	P-384
ECDSA	P-521
Schnorr (EdDSA)	Ed25519
Schnorr (EdDSA)	Ed448
Schnorr (BIP340, "Taproot")	secp256k1
RSA PKCS#1v1.5	2048, 3072, 4096 bit keys
RSA PSS	2048, 3072, 4096 bit keys

In addition, the TSM also supports other cryptographic operations:

Primitive	Parameters	Operations
AES-CTR	Key size 128, 192, 256	Keystream
AES-CBC	Key size 128, 192, 256	Encrypt, Decrypt
AES-GCM	Key size 128, 192, 256	Encrypt, Decrypt
AES-CMAC	Key size 128	Digest
HMAC-SHA2-256	Key size 1-256 bytes	Digest
HMAC-SHA2-512	Key size 1-256 bytes	Digest
RSA OAEP	Key size 2048, 3072, 4096	Encrypt, Decrypt
RSA x.509 (raw)	Key size 2048, 3072, 4096	Encrypt, Sign
ECDH	Curves: secp256k1, P-256, P-384, P-521	Key agreement
RFC 5649	Key size 128	AES Key Wrap with Padding
AN10922	Key size 128	Symmetric Key Derivation

The CMAC, RFC5649 and AN10922 operations are currently only available in the Builder Vault SDKv1. Note that the symmetric operations (AES, HMAC, RFC5649, AN10922) only work for specific threshold settings.

MPC Protocols

Blockdaemon Builder Vault MPC solutions are based on public research (some of which was performed by the Blockdaemon team), this includes protocols from the following research papers:

[MRZ15] Payman Mohassel, Mike Rosulek, Ye Zhang: Fast and Secure Three-party Computation: The Garbled Circuit Approach. CCS 2015: 591-602
[DJNP+18] Ivan Damgård, Thomas Pelle Jakobsen, Jesper Buus Nielsen, Jakob Illeborg Pagter, Michael Bæksvang Østergård: Fast Threshold ECDSA with Honest Majority. SCN 2020: 382-400
[DKLs19] Jack Doerner, Yashvanth Kondi, Eysa Lee, Abhi Shelat: Threshold ECDSA from ECDSA Assumptions: The Multiparty Case. IEEE Symposium on Security and Privacy 2019: 1051-1066

Additional Features

In addition to the cryptographic operations, the TSM has a number of features: