2024-08-21 17:28:07 +02:00

349 lines
15 KiB
Kotlin

/*
* Copyright 2020 ACINQ SAS
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package fr.acinq.secp256k1
import kotlin.jvm.JvmStatic
public interface Secp256k1 {
/**
* Verify an ECDSA signature.
*
* @param signature signature using either compact encoding (64 bytes) or der-encoding.
* @param message message signed.
* @param pubkey signer's public key.
*/
public fun verify(signature: ByteArray, message: ByteArray, pubkey: ByteArray): Boolean
/**
* Create a normalized ECDSA signature.
*
* @param message message to sign.
* @param privkey signer's private key.
*/
public fun sign(message: ByteArray, privkey: ByteArray): ByteArray
/**
* Verify a Schnorr signature.
*
* @param signature 64 bytes signature.
* @param data message signed.
* @param pub signer's x-only public key (32 bytes).
*/
public fun verifySchnorr(signature: ByteArray, data: ByteArray, pub: ByteArray): Boolean
/**
* Create a Schnorr signature.
*
* @param data message to sign.
* @param sec signer's private key.
* @param auxrand32 32 bytes of fresh randomness (optional).
*/
public fun signSchnorr(data: ByteArray, sec: ByteArray, auxrand32: ByteArray?): ByteArray
/**
* Convert an ECDSA signature to a normalized lower-S form (bitcoin standardness rule).
* Returns the normalized signature and a boolean set to true if the input signature was not normalized.
*
* @param sig signature that should be normalized.
*/
public fun signatureNormalize(sig: ByteArray): Pair<ByteArray, Boolean>
/**
* Verify the validity of a private key.
*/
public fun secKeyVerify(privkey: ByteArray): Boolean
/**
* Get the public key corresponding to the given private key.
* Returns the uncompressed public key (65 bytes).
*/
public fun pubkeyCreate(privkey: ByteArray): ByteArray
/**
* Parse a serialized public key.
* Returns the uncompressed public key (65 bytes).
*/
public fun pubkeyParse(pubkey: ByteArray): ByteArray
/**
* Negate the given private key.
*/
public fun privKeyNegate(privkey: ByteArray): ByteArray
/**
* Tweak a private key by adding tweak to it.
*/
public fun privKeyTweakAdd(privkey: ByteArray, tweak: ByteArray): ByteArray
/**
* Tweak a private key by multiplying it by a tweak.
*/
public fun privKeyTweakMul(privkey: ByteArray, tweak: ByteArray): ByteArray
/**
* Negate the given public key.
* Returns the uncompressed public key (65 bytes).
*/
public fun pubKeyNegate(pubkey: ByteArray): ByteArray
/**
* Tweak a public key by adding tweak times the generator to it.
* Returns the uncompressed public key (65 bytes).
*/
public fun pubKeyTweakAdd(pubkey: ByteArray, tweak: ByteArray): ByteArray
/**
* Tweak a public key by multiplying it by a tweak value.
* Returns the uncompressed public key (65 bytes).
*/
public fun pubKeyTweakMul(pubkey: ByteArray, tweak: ByteArray): ByteArray
/**
* Add a number of public keys together.
* Returns the uncompressed public key (65 bytes).
*/
public fun pubKeyCombine(pubkeys: Array<ByteArray>): ByteArray
/**
* Compute an elliptic curve Diffie-Hellman secret.
*/
public fun ecdh(privkey: ByteArray, pubkey: ByteArray): ByteArray
/**
* Recover a public key from an ECDSA signature.
*
* @param sig ecdsa compact signature (64 bytes).
* @param message message signed.
* @param recid recoveryId (should have been provided with the signature to allow recovery).
*/
public fun ecdsaRecover(sig: ByteArray, message: ByteArray, recid: Int): ByteArray
/**
* Convert a compact ECDSA signature (64 bytes) to a der-encoded ECDSA signature.
*/
public fun compact2der(sig: ByteArray): ByteArray
/**
* Serialize a public key to compact form (33 bytes).
*/
public fun pubKeyCompress(pubkey: ByteArray): ByteArray {
return when {
pubkey.size == 33 && (pubkey[0] == 2.toByte() || pubkey[0] == 3.toByte()) -> pubkey
pubkey.size == 65 && pubkey[0] == 4.toByte() -> {
val compressed = pubkey.copyOf(33)
compressed[0] = if (pubkey.last() % 2 == 0) 2.toByte() else 3.toByte()
compressed
}
else -> throw Secp256k1Exception("invalid public key")
}
}
/**
* Generate a secret nonce to be used in a musig2 signing session.
* This nonce must never be persisted or reused across signing sessions.
* All optional arguments exist to enrich the quality of the randomness used, which is critical for security.
*
* @param sessionId32 unique 32-byte session ID.
* @param privkey (optional) signer's private key.
* @param aggpubkey aggregated public key of all participants in the signing session.
* @param msg32 (optional) 32-byte message that will be signed, if already known.
* @param keyaggCache (optional) key aggregation cache data from the signing session.
* @param extraInput32 (optional) additional 32-byte random data.
* @return serialized version of the secret nonce and the corresponding public nonce.
*/
public fun musigNonceGen(sessionId32: ByteArray, privkey: ByteArray?, aggpubkey: ByteArray, msg32: ByteArray?, keyaggCache: ByteArray?, extraInput32: ByteArray?): ByteArray
/**
* Aggregate public nonces from all participants of a signing session.
*
* @param pubnonces public nonces (one per participant).
* @return 66-byte aggregate public nonce (two public keys) or throws an exception is a nonce is invalid.
*/
public fun musigNonceAgg(pubnonces: Array<ByteArray>): ByteArray
/**
* Aggregate public keys from all participants of a signing session.
*
* @param pubkeys public keys of all participants in the signing session.
* @param keyaggCache (optional) key aggregation cache data from the signing session. If an empty byte array is
* provided, it will be filled with key aggregation data that can be used for the next steps of the signing process.
* @return 32-byte x-only public key.
*/
public fun musigPubkeyAgg(pubkeys: Array<ByteArray>, keyaggCache: ByteArray?): ByteArray
/**
* Tweak the aggregated public key of a signing session.
*
* @param keyaggCache key aggregation cache filled by [musigPubkeyAgg].
* @param tweak32 private key tweak to apply.
* @return P + tweak32 * G (where P is the aggregated public key from [keyaggCache]). The key aggregation cache will
* be updated with the tweaked public key.
*/
public fun musigPubkeyTweakAdd(keyaggCache: ByteArray, tweak32: ByteArray): ByteArray
/**
* Tweak the aggregated public key of a signing session, treating it as an x-only public key (e.g. when using taproot).
*
* @param keyaggCache key aggregation cache filled by [musigPubkeyAgg].
* @param tweak32 private key tweak to apply.
* @return with_even_y(P) + tweak32 * G (where P is the aggregated public key from [keyaggCache]). The key aggregation
* cache will be updated with the tweaked public key.
*/
public fun musigPubkeyXonlyTweakAdd(keyaggCache: ByteArray, tweak32: ByteArray): ByteArray
/**
* Create a signing session context based on the public information from all participants.
*
* @param aggnonce aggregated public nonce (see [musigNonceAgg]).
* @param msg32 32-byte message that will be signed.
* @param keyaggCache aggregated public key cache filled by calling [musigPubkeyAgg] with the public keys of all participants.
* @return signing session context that can be used to create partial signatures and aggregate them.
*/
public fun musigNonceProcess(aggnonce: ByteArray, msg32: ByteArray, keyaggCache: ByteArray): ByteArray
/**
* Check that a secret nonce was generated with a public key that matches the private key used for signing.
* @param secretnonce secret nonce.
* @param pubkey public key for the private key that will be used, with the secret nonce, to generate a partial signature.
* @return false if the secret nonce does not match the public key.
*/
public fun musigNonceValidate(secretnonce: ByteArray, pubkey: ByteArray): Boolean {
if (secretnonce.size != MUSIG2_SECRET_NONCE_SIZE) return false
if (pubkey.size != 33 && pubkey.size != 65) return false
val pk = Secp256k1.pubkeyParse(pubkey)
// this is a bit hackish but the secp256k1 library does not export methods to do this cleanly
val x = secretnonce.copyOfRange(68, 68 + 32)
x.reverse()
val y = secretnonce.copyOfRange(68 + 32, 68 + 32 + 32)
y.reverse()
val pkx = pk.copyOfRange(1, 1 + 32)
val pky = pk.copyOfRange(33, 33 + 32)
return x.contentEquals(pkx) && y.contentEquals(pky)
}
/**
* Create a partial signature.
*
* @param secnonce signer's secret nonce (see [musigNonceGen]).
* @param privkey signer's private key.
* @param keyaggCache aggregated public key cache filled by calling [musigPubkeyAgg] with the public keys of all participants.
* @param session signing session context (see [musigNonceProcess]).
* @return 32-byte partial signature.
*/
public fun musigPartialSign(secnonce: ByteArray, privkey: ByteArray, keyaggCache: ByteArray, session: ByteArray): ByteArray
/**
* Verify the partial signature from one of the signing session's participants.
*
* @param psig 32-byte partial signature.
* @param pubnonce individual public nonce of the signing participant.
* @param pubkey individual public key of the signing participant.
* @param keyaggCache aggregated public key cache filled by calling [musigPubkeyAgg] with the public keys of all participants.
* @param session signing session context (see [musigNonceProcess]).
* @return result code (1 if the partial signature is valid, 0 otherwise).
*/
public fun musigPartialSigVerify(psig: ByteArray, pubnonce: ByteArray, pubkey: ByteArray, keyaggCache: ByteArray, session: ByteArray): Int
/**
* Aggregate partial signatures from all participants into a single schnorr signature. If some of the partial
* signatures are invalid, this function will return an invalid aggregated signature without raising an error.
* It is recommended to use [musigPartialSigVerify] to verify partial signatures first.
*
* @param session signing session context (see [musigNonceProcess]).
* @param psigs list of 32-byte partial signatures.
* @return 64-byte aggregated schnorr signature.
*/
public fun musigPartialSigAgg(session: ByteArray, psigs: Array<ByteArray>): ByteArray
public fun frostSharesGen(seed32: ByteArray, threshold: Int, totalSigners: Int, ids33: Array<ByteArray>): Triple<Array<ByteArray>,Array<ByteArray>, ByteArray>
/**
*
* total signers is deduced from the size of the totalShares array.
* threshold is deduced from the vssCommitments (all vssCommitments should have the same length... which is the threshold)
*/
public fun frostShareAggregate(totalShares: Array<ByteArray>, vssCommitments: Array<Array<ByteArray>>, totalShareCount: Int, threshold: Int, id33: ByteArray): Pair<ByteArray, ByteArray>
public fun frostShareVerify(threshold: Int, id33: ByteArray, share: ByteArray, vssCommitment: Array<ByteArray>): Int
/**
*
* total signers is deduced from the size of the vssCommitments array.
* threshold is deduced from the vssCommitments (all vssCommitments should have the same length... which is the threshold)
*/
public fun frostComputePublicShare(threshold: Int, id33: ByteArray, vssCommitments: Array<Array<ByteArray>>, totalSignersCount: Int): ByteArray
public fun frostPublicKeyTweak(xOnlyPublicKey: ByteArray): ByteArray
public fun frostPublicKeyEcTweakAdd(tweakCache: ByteArray, tweak32: ByteArray): ByteArray?
public fun frostPublicKeyXonlyTweakAdd(tweakCache: ByteArray, tweak32: ByteArray): ByteArray?
public fun frostNonceGen(sessionId32: ByteArray, share: ByteArray?, msg32: ByteArray?, publicKey: ByteArray?, extraInput32: ByteArray?): Pair<ByteArray, ByteArray>
/**
*
* threshold can be deduced from the size of the pubnonces array.
*/
public fun frostNonceProcess(publicNonces: Array<ByteArray>, msg32: ByteArray, publicKey: ByteArray, id33: ByteArray, ids33: Array<ByteArray>, tweakCache: ByteArray?, adaptor: ByteArray?): ByteArray
public fun frostPartialSign(secnonce: ByteArray, share: ByteArray, session: ByteArray, tweakCache: ByteArray?): ByteArray
public fun frostPartialSignatureVerify(partialSig: ByteArray, publicNonce: ByteArray, publicShare: ByteArray, session: ByteArray, tweakCache: ByteArray?): Int
public fun frostPartialSignatureAggregate(session: ByteArray, partialSignatures: Array<ByteArray>): ByteArray
/**
* Delete the secp256k1 context from dynamic memory.
*/
public fun cleanup()
public companion object : Secp256k1 by getSecpk256k1() {
@JvmStatic
public fun get(): Secp256k1 = this
// @formatter:off
public const val X_ONLY_PUBKEY_SIZE: Int = 64
public const val SERIALIZED_X_ONLY_PUBKEY_SIZE: Int = 32
public const val MUSIG2_SECRET_NONCE_SIZE: Int = 132
public const val MUSIG2_PUBLIC_NONCE_SIZE: Int = 66
public const val MUSIG2_PUBLIC_KEYAGG_CACHE_SIZE: Int = 197
public const val MUSIG2_PUBLIC_SESSION_SIZE: Int = 133
public const val FROST_PARTIAL_SIGNATURE_SIZE: Int = 36
public const val FROST_SHARE_SIZE: Int = 36
public const val FROST_TWEAK_CACHE_SIZE: Int = 101
public const val FROST_SESSION_SIZE: Int = 133
public const val FROST_SECNONCE_SIZE: Int = 68
public const val FROST_PUBNONCE_SIZE: Int = 132
public const val FROST_SERIALIZED_PARTIAL_SIGNATURE_SIZE: Int = 32
public const val FROST_SERIALIZED_SHARE_SIZE: Int = 32
public const val FROST_SERIALIZED_PUBNONCE_SIZE: Int = 66
// @formatter:on
}
}
internal expect fun getSecpk256k1(): Secp256k1
public class Secp256k1Exception : RuntimeException {
public constructor() : super()
public constructor(message: String?) : super(message)
}